Just an FYI: You can do this with an email

Email allows "+<suffix>" to be appended to any email.

The usual case is something like "user+testing@site.com", or "user+bills@site.com".

It's a way to auto-tag your incoming mail. You can use one of these "+" suffixes on a per-app basis and then add a spam filter to permanently burn one of them if you get spammed.

I used to do this when I could, but many poorly written email validators reject such addresses. (One service, Rappi, was so gloriously, hopelessly broken that they spammed me now and then at the address with a + in it but I couldn't use it to log in!)

Now I just use Fastmail's masked address feature. (And I do not use Rappi.)

I remember a scheme from the 90s that put a keyed hash in there - and a filter that only accepted valid ones - checked with a key. I think there was an optional date (valid-to).

So you might give someone an address like:

dell-rep-01012027-<hash>@anymail example.com

Isn't that a gmail-only feature?