You're trusting another corp that only handles your email. Not your photos, videos, notes, phones, thermostats, doorbells(?), security cameras, speakers, TVs, youtube income/career...
China has a state issued social credit score. We have a social credit score via megacorps.
https://www.wired.com/story/china-social-credit-score-system...
I'm not sure that drawing a parallel here is actually helping the discussion.
Anyhow yeah: megacorps control is dangerous and frustrating. Unfortunately, splitting all services across several different providers is something that requires lots of conscious effort from all users. And even after you split out everything that you use, you might suddenly realize that there is now a new service provided by one of these megacorps, which you started to use without realizing that it's linked to your main account.
The other soft stuff is fairly trivially backed up and not locked in to any vendor. The devices would need to be replaced, which would be annoying mainly due to cost but would have no long term impact beyond that.
I get your point, but losing my email address would be orders of magnitude more painful for me than those other things.