[gaius]

Free speech does not mean I'm entitled to someone else's platform.

But if a platform wants to be a "common carrier" and not a publisher with all the responsibilities thereof, it doesn't get to make the distinction, so actually in a very real sense, you are entitled to use the platform of anyone who wants to be a common carrier, by definition.

If you send something controversial via USPS, they don't have any liability for it, and only in very exceptional circumstances would it be intercepted in transit. If they were responsible for everything they carried, the postal service would look very, very different. If it's illegal you can be busted at either end but the postal service itself doesn't care.