I think this works in practice but I still prefer to have an anonymous/hidden/random email for each service. If one of your Gmail alias emails is sold, isn’t it trivial to write a script and figure out the real Gmail addresses?
Fair. Feels like it’s an uncommon enough practice that most marketers don’t bother. I had access to a 6,000,000+ email list one time and I was curious how many people did this trick and it was under 100.
It’s possible to initiate from Addy as well. For example, if your Addy alias is example@mailer.me and you wish to email hn@gmail.com then you would send an email to example+hn=gmail.com@mailer.me from the email address registered to the Addy account.
I’m also surprised that slurs/slang/foul language in usernames is allowed unless the server is overwhelmed and things are slipping past the validation.
I think the "validation" is the mods happening to notice (usually because people who create such accounts get flagged, and dang gets notified of flags) and politely telling the person such usernames aren't allowed.
Poor attempt at trying to make the URL unique possibly and prevent it from being blocked. Someone could easily block the domain or use regex to block comments with that domain.