After the second or third (people debate if the third originated there) white supremacism-motivated mass shooting was announced on one of their many "National Socialist" boards shortly before it took place, with the owners refusing to do anything about it, removing them as a customer is more than understandable. The original creator (Hotwheels) had vehemently disavowed and condemned the site and its owners at that point.

Aside from the business impact of tons of customers and the media (rightfully) condemning Cloudflare, and all the potential legal implications, dropping them was the only ethical thing to do. I'm a staunch defender of free speech and opposer of censorship, but when people are being mass-murdered, with more people at risk of being mass-murdered in the future, it's no longer just about speech. At the time of the mass shootings, the majority of boards and posters on the site were supportive of or affiliated with violent extremism and domestic terrorism, and their admins made no efforts to curb that (even if they didn't endorse it). Show me a single US or European company who would still provide infrastructure/networking for them after that point.

Considering their only two incidents of stepping in were that and The Daily Stormer, I'd say they probably have one of the best track records when it comes to freedom of speech and acting as a neutral traffic carrier.