There's no rationale behind that.
The root issue here is that La Liga is able to get a court to shut down a web host. It's shouldn't be anyone's problem but La Liga's that people pirate their stream, but a court let them make it everyone's problem. And there are any number of dumb things the court could have let them do, and turning CF into a utility company that can get shut down by the court doesn't solve the issue.
Finally, the main/original reason CF is useful is because the internet was created naively with no protections against bad actors. Weakening CF just empowers bad actors like LaLiga that much more at the expense of the rest of us. Being able to cloak my origin behind CF so that LaLiga or any other overpowered government or private entity doesn't know who I am is a feature. LaLiga having no option but to throw a tantrum that takes down half the internet is also a feature, and not one we should quickly hand away just because, idk, we can imagine some utopian vision where CF is unnecessary.
You're missing the part where it's a single company, not just "the entire anti-DDoS infrastructure", that's being talked about here.
It would be perfectly possible (no idea how practical offhand) to have an entire ecosystem of competing CDNs all doing the same thing that Cloudflare does, rather than just Cloudflare making those decisions all by itself.
