Open twitter, find any tankie account, and read what they write about kulaks, for example. It is very, very commonplace.

Leftist ideology promotes those things in theory, yes. However, in almost all of my personal and internet interactions with modern western leftists they were arrogant, aggressive and looking for any minuscule reason to openly hate somebody, most often one of their own. And from talking to a lot of other people, those personal experiences of mine are far from unique.