People consider vegans on Lemmy as too preachy. Even in vegan communities here, mods have to remove soooo many inappropriate comments (I read a few of these and they keep getting removed for good reasons). Comments that suggest going vegan on posts about animal abuse are downvoted.
At the same time, whenever there is something about Windows or Chromium based browsers, people here are doing exactly the same. “Just use Linux/Firefox/whatever”.
Yup. This is not a rule, of course, and is just my humble observation, but vegans tend to be really agressive about that stuff. You will never be able to propagate your ideas if you pressure people right from the start of the conversation.