This may be true, but this is a lousy excuse for tolerating Nazis on your platform.
Sure, banning a Nazi from Twitter doesn't actually kill the Nazi. They still exist, they still have Internet access, and they're still filled with hate. But at least they're not on Twitter anymore.
And when AWS sees that they're flocking to a hate site hosted on their platform, there's no reason they have to tolerate it. Sure, they'll go somewhere else, and maybe the hate site will find a new hosting provider, but at least they aren't hosted on AWS anymore.
If we have to play an constant game of Whack-a-Nazi, I vote we whack as many Nazis as we can.