The Daily Stormer shot themselves in the foot by libeling Cloudflare. Before that CF was perfectly willing to give them service, in the interests of being content-neutral provider, despite believing that the site itself was vile.

CF themselves have raised similar concerns about due process in the way they handled this particular case, but I can understand why they dropped a customer against whom they had a pretty strong case for suing.

https://blog.cloudflare.com/why-we-terminated-daily-stormer/