CF could have said to KF "For various reasons we no longer wish to do business with you. In 24 hours we will stop redirecting to your servers. Please make appropriate arrangements." Had they done this, they would not have actually been censoring KF. They would also have been behaving like a responsible service provider by not cutting off service without notice. Instead, they seem to have made the decision to do this…
Cloudflare: "... we believe are potential criminal acts and imminent threats to human life that were posted to the site." No, Cloudflare isn't obligated to continue to provide services to support "potential criminal acts and imminent threats to human life". Perhaps if KiwiFarms had better moderated their content and discouraged such behavior this could have been avoided.
> Over the last two weeks, we have proactively reached out to law enforcement in multiple jurisdictions highlighting what we believe are potential criminal acts and imminent threats to human life that were posted to the site.
In other words, they had plenty of time to give KF notice and terminate the relationship. This didn't even have to stop them from contacting law enforcement. But they did something else instead.