There is a general tendency on the internet that any forum that promotes free speech and only moderates spam and illegal posts, but does not remove posts based on their content, becomes majority right wing after some time. There are left-wing forums with censorship, and there are right-wing forums with censorship, of course. But if you let people discuss their ideas freely without interference, the mostly tend to become right-wing. It seems that without censorship and content-based moderation artificially steering discussion left-wing ideas cannot exist.