I think the issue is whether Cloudflare("CF"), as an internet infrastructure, should be involved in balancing free speech with other rights and if so, what kind of bar should they have before deciding to act.
Looking at the issue in this way, your argument that:
> Cloudflair's decision to stop doing business with kiwifarms is a step towards free speech, not away.
may be right and most people would agree. But some people may be more concerned about how CF has reached that decision and the future implication of this action. After all, there is a possibility that CF may have gotten this one right even with inconsistent reasoning/ shaky evidence. In that case, there may be future cases where CF jumps the gun too fast.
Some are also scared about how much (perceived) power CF has over current internet infrastructure. This is understandable as CF is a company and their decision making process isn't as transparent as public system. But if there wasn't such dominance by CF and it was merely one of many competitors, this wouldn't be a big contention.
TL;DR People are arguing about different things: short term result and long term implication. You can agree with the banning of Kiwifarm but still be concerned about how CF reached that conclusion.