Definitions aside, you're just listing "groups" or "ideologies" or whatever you want to call them and then acting like you can objectively determine which are acceptable and which are not. That's also what reddit is doing.

Look, I think Nazism is wrong, I think cops should stop shooting black people for no reason, and I don't really know what "Antifa" is. But I think all of these groups should be able to have subreddits.

I could argue about definition here, and based on your own definitions, "Antifa" might be advocating violence. That aside, the real issue here is that this whole thing seems dishonest to me.

Reddit is banning stuff that generates bad PR. They're banning things that aren't mainstream and things that could be portrayed as advocating/glorifying violence. They aren't going to ban a subreddit for advocating war with North Korea/X country. They aren't going to ban a subreddit for encouraging people to beat up Nazis.

Reddit can do what they like, but I think it's a bad call.