No thank you, I don't want a mandatory backdoor for every government that might want to claim jurisdiction over one of those large worldwide providers.

No. I have a domain precisely because of avoiding a monopoly, duoplily, oligopoly on my email. Any service that required this would have me walk. The footsteps of a single zhte415 may not be loud, but I feel, especially in tech, I would not be alone.

Great, if we do this, we've done to e-mail addresses (and domains) what we've done to phone numbers. Some phone numbers, because of the carrier serving them, are "less than" others out of some (mistaken) idea that it's easier to get a bulk-load of phone numbers from some kinds of carriers and not others.

And then, what do you do when a new provider wants to join the scene? It already takes a year of process and documentation for a new certificate authority to get into most browsers and even then the adoption will be years in the making because most devices don't get root certificate updates. What's the process like for e-mail in your hypothetical? Does Hey.com not even bother because getting buy-off from even the top 50 account-based web sites takes forever?

> Good practice for users in general is to use email services like gmail as thier login/account email and add thier custom domain emails in thier bio.

Absolutely not. The entire point for using my own domain is so my identity is not irrevocably tied to Google. When Google can, and does, nuke my account from orbit on a whim due to some perceived slight, I have no recourse. I can't even sue because of the mandatory arbitration clause they slapped in their several-thousand-word terms of service.