IRC isn't a "platform", but you started here:

> Every message board and chatroom (bbs, forums, irc, icq, aol, et all) on the young internet was virtually uncensored and a 100% free for all

But if your definition of "virtually uncensored" is that there are uncensored instances, then IRC, forums, etc. are just as "uncensored" as ever. There's just a lot more internet users on moderated platforms now.