It's not about amplifying someone. There is a difference between ignoring someone and silencing them. Cloudflare's move seems more like silencing than ignoring to me. Maybe I'm too optimistic, but I think everyone should be able to put their (sometimes terrible) opinions on the internet, and we'll trust society to decide which ideas are terrible and should be ignored.

CF terminating their service absolutely does not silence them. They have many other ways to get their message out, even ways that look identical to what CF was providing.

If they end up actually getting turned away everywhere, and have no avenue to get their message out, then perhaps that's saying something about what everyone else things of the quality of their message.

And yes, this sort of thing needs to be decided on a case-by-case basis. If every internet company decided to disallow accounts held by people of a particular ethnic group, then that would be a problem. But I don't see an issue with every internet company deciding they don't want to participate in spreading hate speech and giving a hate group a platform to spread their propaganda. We wouldn't be arguing about this if we were talking about shutting down a website distributing ISIS recruitment videos, would we?

For what it's worth, yes, I would still argue that ISIS recruitment videos should be allowed on the internet. (But I could see my future self renouncing this as immature and un-nuanced.) Because in general, I am more afraid of overreaction to terrorism than terrorism itself.

That's true that there are alternatives to CF. As long as there is at least one anti-DDoS provider with an "everyone is welcome" attitude, I suppose CF can do whatever they want. So I'll concede that point.

Cloudflare is refusing to help someone spread their message. Again, if you call that censorship, then I'm not sure where you draw the line, as almost every speech act involves taking space away from other speech acts. Particularly when you're talking about sites like Daily Stormer, which are explicitly used to organize acts of censorship against voices they don't like.

I don't think one can coherently take a neutral stance at that level. If not helping Daily Stormer disseminate their message is branded as censorship, but Daily Stormers acts of bullying and threads of violence are not, then I would say that that definition of censorship needs to be re-evaluated.