Oh, here's a thing you could've googled: https://www.reddit.com/help/contentpolicy/

I was sarcastic to you because your question was answerable in ten seconds of googling, which suggests to me an insincere line of questioning.

Well, acceptable discourse is often used as a vague pretext for censorship. And Googling of "acceptable discourse Reddit" doesn't have much useful result. It's good to clarify the specifics.

They should be same as everywhere, and when your community becomes fixated on a conspiracy involving Hilary Clinton, Podesta, and a pedophile sex ring you should stop and ask:

"How far have I strolled from the herd?"

So basically they have different views, and thus bannable.