The censorship isn't arbitrary though. People don't understand the underlying pattern because they think of Reddit as a free speech free-for-all, when really it is fundamentally based in libertarian principles of property rights. The idea is that the mods and subscribers of a subreddit have absolute control over their subreddit and the absolute right to the integrity of their subreddit community, in the same way that people in the real world have an absolute right to their property. The admins only oppose censorship as a policy insofar as it interferes with this right (so banning a sub just because they have offensive content would be against the principles of Reddit). However, if certain communities are interfering with the culture and functioning of other communities (violating the non-aggression principle, so to speak) or posing a threat to the site as a whole, then they can and do get banned.A large portion of the exodus is just people tired of arbitrary censorship.