vegantheoryclub.org is vegan run.
Also personally I've had issues with precisely one user on hexbear (the one who accused me of being db0 in disguise lol) and none from ml. I don't always agree politically, but that's true for every lemmy instance.
Tbh I have difficulty understanding the drama around them. Hexbear in particular is fantastic for vegans (vtc aside) as their COC specifically requires certain vegan-forward stances, which they recognise as part of a liberation struggle.
Holy shit actual facts.
I've avoiding arguing about this because I'll just be drowned out but gotta say it's worn on me the amount of people calling us hiltlarian dictators because we gasp want to let vegans post vegan shit without constantly having to defend themselves.