I think you assume this detail is widely known about the affair, but I didn't know about it.

Here's an article from the time describing what happened: https://gizmodo.com/cloudflare-ceo-on-terminating-service-to...

Importantly:

“I realized there was no way we were going to have that conversation with people calling us Nazis,” [CloudFlare CEO Matthew] Prince said. “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.”