Hm, that fails to land as a criticism. Depends whether you're talking about (a) "free speech, the legally-protected institution" or (b) "free speech, your right to be awful and not suffer consequences". The xkcd is saying that people saying "but my free speech!" are defending (b) by describing it as (a), which it's not. That's basically true. Afaik the part xkcd definitely gets wrong is the part about "can't arrest you for what you say", which isn't really how it works (for instance https://www.popehat.com/2016/06/11/hello-youve-been-referred... discusses the case of how it enters into civil suits).

Of course _philosophically_, yeah, the people who included (a) in the constitution were interested in (b). Everyone's on board with free speech as a concept here. But at some point if someone is yelling Nazi stuff, I'm gonna punch them for it. It's not a legal question at all; my actions aren't governed by laws, just what I feel is right to do. That is the same point xkcd was making. I don't know enough to say whether AWS or whoever has the same right because they are operating in a legal system. But as a _person_, yeah, I can do whatever I want to you, including 'show you the door', if you're awful.