Still not seeing how that's any different from DNS. I mean yes, obviously it's another possible point of failure. But I don't see MITM protection as being any less important than name resolution on the modern web. Seems no less reasonable for a site to break due to lack of MITM protection than for it to break due to failure of name resolution. Normal users aren't going to be manually looking up and navigating to IP addresses anymore than they're going to be manually installing TLS certificates.