No, absolutely nothing wrong with setting ambitious and unreachable targets. Reach for the stars and you might at least get to the moon, etc. But if you say "I'm an effective altruist" then you are claiming to actually be effective and if you say "our movement is Rationality" then you are claiming to be paradigmatic examples of actually being rational, and I think that's a bad idea because it should be possible to say "I'm part of such-and-such a movement" without making that kind of claim.
Oh yeah, I don't think anyone should claim to be effective or rational, per se. Fwiw the original Sequences make it very clear that a rationalist is supposed to be somebody who pursues rationality, rather than possessing it.
So you say it should be possible to avoid making this claim. I agree, and I believe Eliezer tried! Unfortunately, it was attributed to him anyway.
Right. And I think that using "Rationality" as a name for the movement as opposed to its goals does amount to making that claim, which is one reason why (so far as I can see) EY never actually uses the word in quite that way and I don't think others should either.