Over the course of the past year I've been noticing more and more subreddits disallowing comments and posts from new accounts.

Right now I think it's impossible to post into any popular sub with a throwaway.
I just wasted my time typing a long answer to someone and it's automatically rejected. And I'm not going to bother asking the mods for permission to talk every time.

What's going on? Reddit uses Google's brand new Captcha that's nearly impossible to override with a bot.

Is this part of a new censoring campaign or something? Making it harder for people to stay anonymous? I don't see any other reason.
I thought this website was about free speech, open to new ideas etc.

Right now it seems like I have to go through a few days worth of tests and wait for the admins to agree with what I say before I'm allowed to talk.