the statement is very nearly meaningless. The hedging doesn't so much seem like a realistic set of qualifications to the statement "I endorse this" because there's no analysis;
I agree that statements of the form "I'm in favor of a policy towards X, though a lot depends of the implementation" can often be pretty hollow - except that in this case I don't expect everybody to recognize X as a worthwhile goal, so it's a way to keep the discussion about abstract goals rather than concrete policies. If people don't agree about the goals, discussing the policies is premature.
it looks a lot more like leaving onself a line of argumentative retreat. "I'm for that, unless it becomes so wildly unpopular later that I feel the need to retract the statement for social signalling reasons."
Nah, eugenics are already quite unpopular (though not particularly among online nerds like us) but I find the principle perfectly reasonable, so I don't think social signaling is playing a huge role here. It's more like "I'm for that, but of course there can be some bad implementations, so I don't need someone to come up and say 'hey but what if there's a bad implementation?'", it wouldn't be a very productive discussion.
So saying "I'm for this, depending on how it's implemented" seems to ignore that in any realistic case it's quite likely to be implemented quite badly
Couldn't the last bit be said about nearly any policy proposal? Plenty of policies that sound good on paper turn out to be trainwrecks, or at least to have a pretty crappy cost-benefit ratio.
There are three basic positions on a policy towards "poor people should have fewer children, rich people more"
A: It's a valid goal, why isn't it done already?
B: It's a valid goal, but the implementation is going to suck, so no.
C: It's not a valid goal, don't do it
I expect a large chunk of the public to lean towards C; I lean towards A or B depending of the details, and you seem to lean mostly towards B. I'm vague about A or B not because I want to be able to claim B once it turns out to be unpopular (as far as I can tell, A and B are already unpopular among non-nerds), but because I think the distinction from C is more important, interesting and easy to discuss.
Does that make sense? Have I misunderstood or misrepresented you?
I recently read an article by Steve Sailer that reminded me about something I have been puzzled by for a long time. Relevant paragraphs:
Poor people having fewer children means that the children have more resources available per capita making the children better off. Rich people having more children actually increases equality in society since it reduces the per capita resource advantage their children have. Rich people giving to their children is also one of the few cases where the redistribution of wealth doesn't reduce incentives for wealth creation. Rich people care about their children too.
Since programs aimed at reducing teen pregnancy rates do seem to have had some effect, we known something like this is possible without being horrible to the potential parents it targets.
Yet a policy of "poor people should have fewer children, rich people more" sounds heartless despite increasing general welfare both by making poor children better off and by reducing the privilege of rich children thus increasing equality which we seem to think is ceteris paribus a good thing.
Why is that?
Edit: To test the source of the reader's intuiton (assuming he shares it with me), I encourage the consideration of two interesting scenarios that may depart from reality.