As a counter-anecdote, about half a year ago a a self-described 'Alt Right Trump supporter' posted, and I posted a comment asking him about his beliefs, since I had only heard people hating on 'Alt Right' from my own sources, and was curious why he believed what the believed. You can see it here:

https://news.ycombinator.com/item?id=12971897

So not everyone here tries to silence alternate viewpoints, at least.