It's not valid, that's how. He's using "free speech" as a way to hype up all the right winger fanboys and to unban people who will cause incredible drama (i.e. engagement) on Twitter. Hopefully all it causes is online drama, but the barrier between real world actions and online information sphere is way more permeable than the "it's just a website!" people would have you believe.

It has nothing to do with principles of any sort.