Because they don't _control half the internet_. They only have one service you use, not 50. Your phone (voice), cloud storage (drive), website hosting (sites), chat (not even gonna try), music streaming (YouTube music), video hosting, etc aren't all dependent on the same single point of failure like they are with Google. All your mail provider can do is stop processing your email for you (at which point you switch providers). If Google doesn't like you, you lose _all_ of those things, likely all at once. Google even has a hand in your credit card transactions with Google Pay (though anecdotally, I've never actually seen anyone use Google Pay, so not sure how many people that would affect). Google provides such a diverse range of services that having them all shut down on you is a huge deal. I'm currently in the process of looking for a replacement for my legacy Google apps account, and that's just email.