At some margin I think this would become an important consideration (e.g., advocating some policy that made being non-vegan super expensive) but at the current margin it seems like these costs are just extremely small relative to the suffering reduction they induce.

Is there a cost-effectiveness analysis that takes these costs into account? I don't think I've seen one.

What specifically in farmed animal welfare do you think beats GiveWell? (GiveWell is a specific thing you can actually donate money to; "farmed animal welfare" is not)

Farmed animal welfare is politically controversial in a way that GiveWell is not. This is potentially bad:
- Maybe people who don't care about farmed animals are correct
- Farmed animal advocacy is so cost-effective because, if successful, it forces other people (meat consumers? meat producers?) to bear the costs of treating animals better. I'm less comfortable spending other people's money to make the world better than spending my own money to make the world better
- Increased advocacy for farm animals might just cause increased advocacy for farms, just burning money rather than improving the world
- It's hard to be as confident in political interventions - humans and groups of humans are much less predictable than e.g. malaria
- Farmed animal welfare sometimes seems overly-connected with dubious left-wing politics (e.g. https://forum.effectivealtruism.org/posts/5iCsbrSqLyrfP55ry/concerns-with-ace-s-recent-behavior-1)

This kind of deal makes sense, but IMO it would be better for it to be explicit than implicit, by actually transferring money to people with a lot of positive impact (maybe earmarked for charity), perhaps via higher salaries, or something like equity.

FWIW this loss of control over resources was a big negative factor when I last considered taking an EA job. It made me wonder whether the claims of high impact were just cheap talk (actually transferring control over money is a costly signal).

Yeah, that explanation seems right. But - the high-decoupler rationalists are the counterexample to your claim! That group is valuable to EA, and EA should make sure it remains appealing to them (including the ones not currently in EA - the world will continue to produce high-decoupler rationalists). Which is not really consistent with the strong norm enforcement you're advocating.

99% is really too high. It's more than 1% likely that you're just in a very strong ideological filter bubble (which are surprisingly common; for example, I know very few Republican voters even though that's roughly half the US). The fact that this is a strong social norm makes that more likely.

I already said this, but I don't really understand how you can be so confident in this given the current controversy. It seems pretty clear that a sizeable fraction of current members don't agree with "saying "different races have different average IQs" is irredeemably racist". Doesn't that disprove your claim? (current members are at least somewhat representative of prospective members)

I think a historical strength of EA has been its ability to draw from people disconnected from mainstream social norms, especially because there is less competition for such people.

in an environment where prospective members and funders almost universally believe that saying "different races have different average IQs" is irredeemably racist

Is that true? I am skeptical. Notably, this seems to be controversial among the current membership (which is exactly what OP is complaining about!)

A majority oppose the electoral college (which gives unequal weight to different people). https://www.pewresearch.org/fact-tank/2022/08/05/majority-of-americans-continue-to-favor-moving-away-from-electoral-college/

Some quick thoughts:
1. Rich country politics are not very neglected. Lots of resources are spent on them, and it's not clear EA would make too much difference. Maybe now that EA is bigger it's more plausible?
2. I think there are a number of groups pursuing this kind of vision;  the DSA in the USA sounds rather similar to what you envision, from what I know of them. What would remain distinctive about EA if it became another left-wing political group?
3. IMO within-country inequality is a much less serious problem than between-country inequality (because rich countries are ~100x richer per capita than poor countries). You seem to equate "poverty" in Zimbabwe and the UK, but they are not equivalent - practically no one in rich countries is in extreme poverty (under $1.90/day); the poverty lines in rich countries are for a much higher standard of living.
4. Improving political institutions in poor countries would probably be very valuable, but it seems really unclear how to do it. I'm skeptical that making the US less unequal or more democratic would help much.
5. EA does invest quite a bit in community building, and AFAIK there are quite a few local groups similar to your (2)
6. I personally have some doubts that goals like "decrease inequality in rich countries" are actually desirable. There's a reason these questions are live political debates! Most EAs are left of center, so perhaps you could get pretty good consensus on some things like this, but I'm not sure the cost of alienating people who disagree is worth it - I'd actually like to see more right-of-center EAs.
7. EA does do some political work already. Here's immigration: https://www.openphilanthropy.org/focus/immigration-policy/. Here's reducing US incarceration: https://www.openphilanthropy.org/focus/criminal-justice-reform/. Here's YIMBYism: https://www.openphilanthropy.org/focus/land-use-reform/. Here's monetary policy: https://www.openphilanthropy.org/focus/macroeconomic-stabilization-policy/. 

As FTX just spectacularly demonstrated, Will was wrong. This is because even though FTX was ostensibly started with the sole goal of making a profit, it turns out there were other important implicit goals like “don’t steal billions of dollars from thousands of people”, implicit goals like that always exist, and failure to meet those implicit goals is very bad.