[aziaziazi]

Fair enough. I see your point on the limits of interpretation and how any philosophie ends up being somewhat arbitrary.

You still choose a frame (eg: "killing any animal is wrong"), then show that frame is irrational and deduct that the while group is wrong. Classical strawmaning, although I'm sure that's not your intent. "Animals needing to die" as a practical truth is not a problem for vegans, you're arguing alone here. However many people thinks suffering is not desirable and act accordingly to minimise it. You're free to critic though.

I understand better your second explication: there's not more absolute anti-specism than absolute freedom of speech. I find more interesting the "All models are wrong, but some are useful" perspective as it helps interacting with the world, but in a theorical land you're probably right.

If you haven't read it and want to learn more, a good one is https://en.wikipedia.org/wiki/Animal_Liberation_(book)