First: check whether the issue is really important: With some exceptions (voting correctly, believing the correct afterlife and not getting sent to hell) If you aren't in a position to interact with the evidence it's probably not something you meaningfully have control over. (Most things for which it is important for you to personally understand have measurable consequences to you. Why do you need the right answer to the GMO question, what would you even do with the right answer?).

Then:

-Figure out exactly what the claims really are and try not to conflate different claims (GMOs will do what, exactly?)

-Consider the possibility that the entire premise is silly ("Is God one or trinity?" "Is she a witch?") and the "consensus" is just wrong and the debate is insane. Generate some plausible third options.

-Check if the two hypotheses seem by your perception to be of roughly equal parsimony, internal logical consistency, and compliance with known evidence, and also check the third options you generated.

-Ask the basic "so, what evidence would you need to tell the difference" questions.

-all the things you mentioned (weigh expert opinions, eliminate bad arguments, eliminate experts who use bad arguments)

-look for concrete predictable things in that area, and adjacent to that area which differ according to the two hypotheses.

-If it's a political issue, try to find out what people who might plausibly be expertish in the area yet don't seem to be invested in debating the issue think about it.

-check what known superforcasters in the field think (people who have a track record of successful predictions in that area). Superforecasters need not actually be loudly engaging with the issue, just ask.

-check if people who have different types of knowledge tend to say different things (e.g. economists vs. sociologists)

-What sorts of knowledge would you need to have to answer the question vs. what sorts of knowledge do the experts in question actually have? (You might think medical doctors are qualified to talk about the effectiveness and safety of various treatments, for example, but they aren't. You want a medical researcher for that. The only difference between a medical doctor and a witch doctor is that one was trained by a curriculum developed by medical researchers and the other wasn't.)

-check for founder effects or cultural effects biasing beliefs (Again, economists vs sociologists. Also, if theologians believe in god at higher rate than biologists it might not be because of different knowledge)

What else? I mean it's a big question, you've asked after a fairly big chunk of "rationality" there.

Can you be more specific about what you are calling GMO?

In a world of labeling I have no problem with having more specific labels for different types of it.

And what you are saying is the problem?

Goodhard's law is generally a problem when you have strong optimisation tools.

With unlabeled GMO's the commercial pressure is to create food that is as cheap as possible without regard for whether it's healthy. If you require labeling than the companies producing the food have incentives to produce healthy food.

GMO's reduce diversity of agriculture. That produces a systems that generally less robust, for reasons that Nassim Taleb talks about frequently.

Golden rice - probably fine.

Do you believe that people shouldn't know whether or not their rice has added Vitamin A? I think it's very worthwhile for people to know about it.

Here's a little example of prisoner's dilemma that I just thought up, which shows how mass media might contribute to modern loneliness:

Let's assume that everyone has a fixed budget of attention and empathy. Empathizing with imaginary Harry Potter gives you 1 point of utility. Empathizing with your neighbor gives them 10 points of utility, but doesn't give you anything, because your neighbor isn't as interesting as Harry Potter. So everyone empathizes with Harry Potter instead of their neighbor, and everyone is lonely.

Does that sound right? What can society do to get out of that trap?

Slightly of topic, but relevant. Nothing in this nor any of the comments mentions what percent of your "happiness level" might be expected to come from a form of spending money. Presumably, some significant percentage of your happiness comes from things that do not directly involve spending money.

You cannot have a true idea of how much happiness money can buy if you do not adjust (downward) the value of money-bought-happiness based on the fact that it will account for only a portion of your happiness pie chart. Most of us do this to some extent, automatically weighing in the value of an extra hour of sleep or hour of unstructured family time into our happiness calculations, but if you are looking to maximize your happiness you should look at non-money sources of happiness as rigorously as you do moneyed.

Assuming that you are engaged in conversation/argument/debate with a specific target, perhaps the best way to edit out spurious strawmen is to mentally append "except in this case...." to any objection.

Thus:

Them: "It's important to be yourself."

You: "Except in this case, because John is a psychopath."

(Or, You: "Except in this case, because John is a fine, upstanding young guy... oh... nevermind.")

Not only should this eliminate most straw men, it should help keep the discussion on track.

It does mean that not-scams should find ways to signal that they aren't scams, and the fact that something does not signal not-scam is itself strong evidence of scam.

Overcoming Eager Evidence

Does anyone know any good way to make a point that one believes is true on its own merits but clearly benefits the speaker or is easier for the speaker?

Suppose a poor person is saying we should all give more money to poor people, are there ways to mitigate the effect of “You're only saying that to benefit yourself” beyond either finding someone else without that perceived (and likely actual, but maybe less than perceived) bias or just taking the hit and having a strong enough case to overwhelm that factor?

Depends if you like cooking, and if you have the time to do it properly. There's a reason you pretty much only see childless folks Instagramming dinner.

I think money prevents certain types misery more than it buys happiness.

For example, flights with stopovers and shitty public transportation make me miserable and usually sick. By spending money on direct flights and taxis, I save myself many days of life that would otherwise be lost (I have to travel a lot).

Similarly, knowing I can afford good medical care if I get sick, or find a new apartment if mine becomes unpleasant, or send my kids to a private school if public schools are too useless... these things don't make me deeply happy, but if they were not true, that would make me constantly anxious.

Money is a cushion against disaster. If something goes awry, you can use it to buy medical or legal or technical assistance. However, for me personally it does not cause an actually happy or joyful affect, nor does it seem to buy the things that do (except very indirectly).

Think about the things you use very often and/or for extended amounts of time. Buy the highest quality version of that that you can afford. For example shoes, chairs, beds, at any one time you will be in one of the three, so buy the best you can afford. Donating to a feel-good charity might also improve your happiness. The exact amount seems to be irrelevant.

Edit: Another possibility is to buy more than you actually need of items you use, like having multiple nail clippers at multiple locations for convenience instead of having to carry out one specific nailclipper.