https://robindev.substack.com/p/cloudflare-took-down-our-web... - one of a number of citations. To find more insert the terms [Cloudflare, hostage] into your favorite search engine.
Cmon, this is the guy that was running a shady online casino which was tanking Cloudflare’s IP reputation, completely different.
Whatever was really happening in that incident it seems clear that it was not a simple matter of having registered some domains with Cloudflare and then getting a shakedown for $100k+ because of that.
If anyone else chooses to read the post then I suggest skimming the comments (that are mostly hidden by default) as well.