But if they kill your access to those accounts do you have a method to force them to let you back in to get “your” content? Serious question as I self-publish and use a distribution service for my music but I stop short of your claim. I’m an independent rights holder. I don’t own the platforms upon which I choose to distribute my work - terminology does matter and, well, you’re claiming something basically untrue because it sounds cool…that’s my impression.
Why would he need to be 'let back in to get' his content? This is a static site: he's already got it.
As long as domain control isn't lost, he can quickly move from Github to Gitlab/gitee/self hosted and from CloudFlare to Netlify/DO/AWS.