I agree with that, but the distribution of where you have things makes it a bit more difficult. If I have amazon hosting my domain, email, website, and I shop there, then me getting banned because they didn't like me returning too many things will affect everything else. Having my domain at No-IP, Email at fastmail, website self hosted means that Microsoft banning an account I use won't affect any of that.
If your domain gets stolen then you're similarly out of luck. You now need to change your email on every website you use, which for many requires email confirmation or contacting support.
