No, I see vegans who think they're better than everyone else by virtue of their veganism as insufferable. I've no issue with vegans who keep to themselves I would welcome a world of impossible meat should we get to that point and encourage a switch to more sustainable diets as allowed by our infrastructure, but we're simply not there
Vegans are a yellow flag to me because most of the times, when someone comes up to me unprompted to talk about how eating animals is bad, they're assholes about it. I was approached here, unprompted, in my comment about liking animals in a post about green flags. If their veganism comes up when I offer food and they just say they don't eat that, that's no problem. That's why it's a yellow flag. Veganism isn't bad, it just has a bunch of annoying pricks in it that make 'em all look bad
So yeah, just to be clear, I do not oppose veganism. Veganism is a yellow flag because very often they bring it up out of the blue just to get on their high horse