Further reading indicates that it just someone posting on their forum. User-generated content is hard. Cloudflare users should make sure to censor what gets posted on their sites if it refers to the political opinions of Matthew Prince.

https://gizmodo.com/cloudflare-ceo-on-terminating-service-to...

>“The Daily Stormer site was bragging on their bulletin boards about how Cloudflare was one of them and that is the opposite of everything we believe. That was the tipping point for me.”