The key difference between the old vegans and the new vegans is hiding in plain sight. It's the Internet. It used to be that vegans went to vegan restaurants and had their own particular tradition of vegan cookery. People didn't just become vegan in isolation like they do today. The acculturated vegans still exist and I think that's who gp is referring to in that statement. The Internet vegans are different but they aren't that numerous — few people even today would make such a change in their life based on something they read online.