Effective altruism is based on the core belief that all people count equally. We unequivocally condemn Nick Bostrom’s recklessly flawed and reprehensible words. We reject this unacceptable racist language, and the callous discussion of ideas that can and have harmed Black people. It is fundamentally inconsistent with our mission of building an inclusive and welcoming community.
— The Centre for Effective Altruism
Who supports this? This is an extremely radical proposal, that I also haven't seen defended anywhere. Of course sentient beings don't count equally regardless of their species, that would imply that if fish turn out to be sentient (which they might) their moral weight would completely outweigh all of humanity right now. Maybe you buy that, but it's definitely extremely far from consensus in EA.
In-general I feel like you just listed 6 different principles, some of which are much more sensible than others. I still agree that indifference to location and time is a pretty core principle, but I don't see the relevance of it to the Bostrom discussion at hand, and so I assumed that it was not the one CEA was referring to. This might be a misunderstanding, but I feel like I don't really have any story where stating that principle is relevant to Bostrom's original statement or apology, given that racism concerns are present in the current day and affect people in the same places as we are. If that is the statement CEA was referring to, then I do withdraw that part of the criticism and replace it with "why are you bringing up a principle that doesn't seem to have much to do with the situation?".
And then beyond that, I do indeed think asserting there is no difference whatsoever in moral consideration between people seems pretty crazy to me, and I haven't seen it defended. I am not that familiar with Bentham's exact arguments here, and I don't think he is particularly frequently cited (or at least I haven't seen it). I also think I haven't seen most of the other philosopher's cited here except Singer, and I would be happy to have my first object level discussion now about whether you think a principle of perfectly equal moral consideration should hold. Singer has gone on record thinking that indeed different people have different moral weight, and this is one of his most controversial beliefs (i.e. his disability stuff is a consequence of that and has in the past gotten him cancelled at various universities), so I don't know what you are referring to here as the principle, though I also feel pretty confused about Singer's reasoning here.
In-general I think we discuss the differing moral weight of different animals all the time, and I don't see us following a principle that puts sentient/conscious beings into one large uniform bucket.