Given how likely it is in the future that we're going to see more Christchurch like 'livestream terrrorism', combining media spectacle with violence this is completely reasonable. If there's indication that you may use Twitch for that kind of thing not letting you on the platform makes sense.

We need to stop throwing 'cancel culture' at everything. If you're known to be an advocate of violence or a lunatic they don't let you on public television or radio either.