While I agree with this distinction, I'm not entirely sure that this is wholly accurate.
The situations in which Cloudflare might have to intervene with legal content are probably pretty limited (e.g. content that would be legal, yet very controversial, or expose something about the company or something like that), but it's still possible.
As a thought experiment, consider a situation in which a person might be using a Russian CDN and would be hosting content about Ukrainian refugees (no intentions of getting political here, it's just a good example) - now I'm pretty sure that Russia might just make it illegal, but even without it being explicitly legal, a few strings could be pulled and the service to that site shut down. What about a Chinese CDN that expresses views that are different than the ruling government would approve of.
Maybe there should be an asterisk there - depending on the nature of your content, have both the services you use and the platform that you own be somewhere, where it won't cause problems.
You cannot move from Twitter to SomeOtherUnknownPlatform.com or from the App Store to UnknownAppStore.com if those platforms decide they don't want you there. Well you can, but no one will ever see you again. You cannot even move to a well known platform in case your followers are not there (or don't use that OS). At least, it will take years to move them over.
It depends entirely on how many of their offerings you choose to use: https://www.cloudflare.com/cloudflare-product-portfolio/
That's like saying that your application that is running in AWS can easily be moved elsewhere, but that's going to be true only sometimes: a lot of the time you'll use their managed services (which may or may not be compatible with others), their SDKs for setting up the infrastructure (which may or may not be trivial to migrate) and might end up with a lot of knowledge that's largely only valid within their ecosystem.
But that's mostly because a lot of the larger service providers out there try to expand their market reach and provide lots of different services: like I could go to my domain registrar and get either managed hosting or VPSes.