Buck's comment of "the fact that people want to hide their identities is not strong evidence they need to" struck me as highly dismissive. If people do fear something, saying"well, you shouldn't be scared" doesn't generally make them less scared, but it does convey that you don't care about them - you won't expend effort to address their fears.
But Buck wasn't saying you shouldn't be scared? He was just saying that high burner count isn't much evidence for this.
Precisely, I think he was claiming that p(lots of burners | hiding identity is important) and p(lots of burners | hiding identity isn't important) are pretty close.
I interpreted this as a pretty decoupled claim. (I do think a disclaimer might have been good.)
Now, this second comment (which is the root comment here) does try to argue you shouldn't be worried, at least from Holden and somewhat from buck.
I'm about 99% bivalve vegan (occasionally I eat fish for cognitive reasons). However, I think it doesn't make sense for strongly longtermist individuals in terms of the direct straightforward benefits of veganism. The direct animal suffering is negligable relative to the future. I'm strongly longtermist, but I stay vegan for a combination of less direct reasons like signaling to myself and generally being cooperative (for reasons like acausal decision theory and directly being cooperative with current people).