> Eventually you learn that in the end, the way to validate an email address is to send an email.

In my experience as a user, most people in the end also validate the email address by sending an email, but do no learning.

I don't think an @domain is required if it's an email address on the same mail server.

Wow, that is literally the only reason I would want a TLD

...is there someone out there who did this?

Can you actually attach an MX record to a tld?

That regex is defective. See benchaney's reply above.

One (probably forgotten) reason people validated email addresses with convoluted regexps is that there are multiple (actually valid per RFC) email addresses formats that can do nasty things. Like explicitly specifying a series of mail servers to go through. They're (hopefully) deprecated and rejected by most servers nowadays, though.

Thankfully my email is @@@@@@@.......

I wouldn't say "a few other email providers that have followed suit". As far as I know, that's always been a feature of Postfix, and common with Sendmail before that. And qmail offered "-" for the same purpose (as well as providing a facility for filtering/redirecting mail based on -extensions).

That is fair, but maybe the providers just want to stop account spamming on their sites, can you blame them for that?