If I say "there are people being prosecuted for being black", and present as evidence a bunch of black people prosecuted for theft, fraud, murder, etc., and claim that this justifies my claim because the laws against theft, fraud, murder, etc., are too broad, then it is my responsibility to show how broad the laws are, and how policing and prosecution are effectively looking at people's race rather than their actual behaviour.

If you say "there are people being prosecuted for objecting to immigration", and present as evidence a bunch of anti-immigration politicians prosecuted for hate speech, and claim that this justifies your claim because the laws against hate speech are too broad, then it is your responsibility to show how broad the laws are, and how policing and prosecution are effectively looking at people's opinions on immigration rather than the incendiariness of their rhetoric.

But you aren't doing any of the work required to justify your (prima facie implausible) claim. You're behaving as if everyone's default assumption should be that (1) the hate speech laws are so broad that they make basically everyone who objects to immigration a criminal, and that (2) what on the face of it are prosecutions for hate speech are really motivated by wanting to punish everyone who objects to immigration. I do not think either of those is a reasonable default assumption. I think both are implausible, and I think that if you want us to believe them you should give some evidence for them.

However, I'm kinda losing hope of your ever producing any evidence for any of the claims you make, so I guess I'll have to do your job again.

Consider four possible worlds.

In world A1, hate-speech laws are extremely broad and criminalize a lot of things that don't really involve stirring up hate and resentment and whatnot. This fact is exploited by the law-enforcement system to persecute people who object to immigration, so that such people are likely to get arrested, prosecuted, convicted, and punished.

In world A2, the hate-speech laws are just as broad as in world A, but there is no particular attempt to persecute people who object to immigration. What gets you prosecuted under hate-speech laws is behaving in ways that seem to be stirring up hatred and resentment; because the laws are very broad, some people get in trouble despite not intended to stir up hate and/or not actually succeeding in doing so, but the distinguishing feature of people who get in trouble is something like "incendiary rhetoric" or "throwing broad sweeping insults at large groups of people" rather than "objecting to immigration".

In world B1, the laws are not so broad, but as in world A1 the law-enforcement system is keen to persecute people who object to immigration. So those people are extra-likely to get arrested and prosecuted. Most of them will then be acquitted because the laws don't really criminalize what they've done, but sometimes the persecution is sufficient to get the laws misapplied too and they get convicted.

In world B2, the laws are not so broad and there is no attempt at persecution. The people who get in trouble under hate-speech laws are pretty much the people who are, or would seem to a reasonable person to be, trying to stir up hate and resentment. No system is perfect and some people may get in more or less trouble than the lawmakers intended, but on the whole what happens is that serious efforts to stir up hate get you into trouble and (as far as these laws are concerned) other things don't.

(So A/B is about breadth of laws and 1/2 is about exploitation of the laws to try to persecute people who object to immigration.)

Being good Bayesians, let's now ask how plausible these worlds are a priori and what sort of evidence we might expect to see to distinguish them.

Prior expectations on A/B: it's common for laws to be somewhat too broad, but usually not absurdly so; "hate speech" is naturally a thing with fuzzy edges; I would expect the laws to leave substantial room for discretion (so that e.g. abuse would certainly be possible) but to be drafted in such a way that most things that aren't actually attempts at stirring up hate and resentment would not seem to a reasonable person to be forbidden by the laws. Depending on your overall level of cynicism about how laws are made, you might reasonably have different priors on this one.

Prior expectations on 1/2: the bulk of any such persecution would have to be done by police, public prosecutors, and judges. It looks to me as if these are all groups whose tendencies run much more anti-immigrant than pro-immigrant. So I would be a little more surprised by 1 than by 2.

On either of these, you might disagree (and in fact I bet you do), but what seems clear to me is that there isn't any sort of overwhelming prior reason to anticipate A over B or 1 over 2.

What about evidence?

The clearest evidence for A and 1 would be that people who object to immigration in ways that aren't particularly hate-fomenting suffer actual arrests, prosecutions, convictions and penalties which is why I keep asking you to provide some examples of these. In the A-worlds we should expect actual convictions. In B1 we should expect lots of arrests and some prosecutions but fewer convictions and penalties.
- From the things I've looked at so far, it does not seem that this happens. E.g., I gave a number of examples of politicians being vigorously anti-immigration and not getting into any sort of legal trouble for it, and the examples you have gestured towards don't seem to include any where people have got into legal trouble for clearly-not-hate-fomenting objections to immigration.
We might also see, especially in the 1-worlds, that among people who are in fact trying to foment hate there are disproportionately many arrests/prosecutions/convictions/penalties for people who are also anti-immigration. This may be tricky to assess because if someone hates a particular group we should confidently expect them to oppose immigration by that group. But e.g. racism is often broad, so we might look to see whether people getting into trouble for racist "hate speech" are being hate-speech-y about racial groups that don't do a lot of immigrating to their country.
- Tricky to assess, as I said. But e.g. note that two of the four examples (France and Germany) in that paper about anti-immigration politicians getting prosecuted for hate speech seem to be mostly about antisemitic or pro-Nazi speech rather than anti-immigrant speech. That doesn't look to me like what we should expect if these laws are actually functioning as tools for punishing people for objecting to immigration.
We could look at the actual laws; that should help to distinguish A from B.
- Since it's so central to your argument, I'd have expected that by now you'd have given some examples of over-broad hate-speech laws; but you haven't.
- I took a look at the UK's law, as an example (the UK's because English is my native language; I think the UK is less immigrant-friendly than some mainland European countries so its laws may be less stringent). I think the relevant thing is the Public Order Act 1986, as amended on various later occasions. It has a section on "racial hatred" which seems like the thing we want here. The language it uses repeatedly goes like this: "... he intends thereby to stir up racial hatred, or having regard to all the circumstances racial hatred is likely to be stirred up thereby". (And "racial hatred" is defined as "hatred against a group of persons defined by reference to colour, race, nationality (including citizenship) or ethnic or national origins".
- On the face of it, this prohibits exactly the things that a law against stirring up racial hatred is supposed to prohibit. On the other hand, it's not hard to see how it could be abused; anyone could argue that anything is likely to stir up racial hatred having regard for all the circumstances. But that feels like it's just a fundamental difficulty with any law of this type, which I think is shared with e.g. laws against slander or libel or fraud.
- I don't see any way in which a reasonable person could hold that this law makes it criminal to say "there should be less immigration, because more-homogeneous societies are more stable" or "there should be less immigration, because typically immigrants cost the country more than they bring in economic gains" or "there should be less immigration, because our population density is already too high". So it definitely isn't a law that criminalizes objecting to immigration as such.
- Arguments along the lines of "immigrants from the US are disproportionately criminal, so we should stop accepting them" or "Chinese people tend to be communists and communism is bad, so we shouldn't accept immigrants from China" come on a spectrum of incendiariness, depending not only on what the argument actually is but how it's expressed. I would expect almost all reasonable people to feel that some things along these lines are perfectly legal according to these laws and some aren't, though I wouldn't expect everyone to agree on where the boundary is.
- On the whole, this seems more B than A to me.
We could look at how actual prosecutions have gone: whether the arguments made in court focus on the tendency of any given statement to stir up hate, or on whether it opposes immigration. We could look for signs that arguments nominally about stirring up hate are really trying to draw juries' attention to opposition to immigration. That would need us to look at actual transcripts of court sessions, or something. I'm not sure whether those are available, but I know I haven't seen any and I am betting you haven't either. (So, in particular, it is not plausible that your position is based on evidence of this kind.)

So, anyway, my assessment of the evidence known to me is that this looks more like a B-world than like an A-world, and more like a 2-world than like a 1-world. If you disagree, what would you expect to see that's different in a B-world, and what would you expect to see that's different in a 1-world?

So far the nearest things to a positive argument you've offered are:

that the hate-speech laws are broad. I don't really see how they could be much less broad while still being hate-speech laws; are there any possible worlds in which (1) there are laws against stirring up racial hatred but (2) you would not say that "you get people prosecuted for objecting to immigration", and if so what do those worlds look like?
that some anti-immigration politicians have been prosecuted for hate speech offences. As I've said, on the face of it what they're being prosecuted for is in fact "stirring up hate" rather than "objecting to immigration"; are there any possible worlds in which anti-immigration politicians are prosecuted for hate speech offences but you wouldn't view it that way, and if so what do those worlds look like?