And YouTube doesn't allow free speech. Without regulation, it allows speech as defined as acceptable to YouTube's business. Worse than both regulated speech and free speech is what bad laws like Section 230 ensure: Corporate speech.
As for corproate speech & it's dangers, sites have a right to identity, to shape & grow themselves in ways they think are fit & healthy. That freedom in no way encumbers your right to speech, it doesnt threaten anyone: we all have abundant options for getting our voices out for sharing. We shouldnt all have to listen to whomever wants to yell; free speech doesnt mean every place on the planet must let whomever in to yell as they please. I dont go to a Borders bookstore to get shouted at by religious fringe groups. Bookstores dont have to have copies of books on the shelf, of perhaps these same groups. These defenses are also "corporate speech", the right of Borders Books to maintain their business & shape it. The internet itself rarely cuts anyone off, almost exclusively only under direct legal need, so there's endless options still available; the protest that everywhere, every big site should have to host content seems abominable, uncivil. We have to rely on sites, and a diversity of sites, or perhaps someday more p2p/direct-publish syndication. When a site grow rotten & oppressive, we can & should go vote with our feet, move to other sites.
I agree that unchecked free speech is chaotic & dangerous. Moderation is important, one of the defining characteristics & something we have a lot of diverse different styles & systems for, that we are still learning from. Sites need to be able to host content, without being direct endorsers/directly responsible parties to that content, and they need to be able to say no to content. Without the first, nothing can be shared nor hosted without vast chilling & frighteningly costly & fragile/elaborate safeguards checking each & every word, and eithout the latter all places bece one big room for the very loudest to shout & dominate & control.