No, but vowing to so strongly oppose other people's attempts to maximize global utility, presumably in favor of demanding some other goal,

Ah, I believe I see the confusion now.

I was not vowing to oppose other people's attempts to maximize global utility, except inasmuch as they would force me to do it. I'm generally against people forcing me to do things I'm morally opposed to. But I have no interest in demanding any other goal for everyone, as I think that would be at least as reprehensible.

It was "demand that everyone work together for X" that I mostly took issue with. Maximizing overall utility is really not as bad as a lot of other goals.