> everyone will be so used to certificates changing all the time, and no certificate pinning anymore, so the day were China, a company or whoever serve you a fake certificate, you will be less able to notice it

I'm a computing professional in the tiny slice of internet users that actually understands what a cert is, and I never look at a cert by hand unless it's one of my own that I'm troubleshooting. I'm sure there are some out there who do (you?), but they're a minority within a minority—the rest of us just rely on the automated systems to do a better job at security than we ever could.

At a certain point it is correct for systems engineers to design around keeping the average-case user more secure even if it means removing a tiny slice of security from the already-very-secure power users.