Yes, quite so, and in fact I agree that Cloudflare has a right to do or not do business as they please.
The real, fundamental problem is that the internet has become too centralized, such that a few entities can direct the rest with impunity.
However, I think we can agree that fixing the centralization of the internet at this point is a fool's errand.
I recall recently about a story of how a father got kicked out by Google for uploading some pictures to his Google account. Fundamentally, KF getting kicked out by Cloudflare is the same thing: Customers getting kicked out by companies because of disagreeable content; companies which are effectively gatekeepers to the internet at large.
So the next best way, in the interim, to keep the internet working in some fashion, is to have businesses like Cloudflare not kick customers out simply for saying or having disagreeable things.
With great powers come great responsibilities, as the saying goes.
Only if you accept that corporations should have the same rights as people. To me that makes no sense once the get to a certain scale.
A business can in general refuse to do business with anyone for any reason. There are certain federal restrictions, namely religion, race, gender etc, but outside that refusing to do business with someone is an inherent part of free speech. Advocating for requiring a company to do business with someone they don't want to is advocating against free speech