I have myname.wifename@gmail.com (we use it for bills, children activities, and other family stuff where you can't register more than one email address).
Neither of our names can be confused with a last name and yet I had multiple people writing to it incorrectly, including: as the email attached to a Diners credit card (I called Diners and they asked me what's the right one and "if I don't know the right one how do I know that it's wrong"), as the email for a school 400 km from home (another family must have had the same idea), once for some lawyer stuff (I then learnt that about 100 people in Italy do have my wife's name as a very uncommon last name), and lately as the recovery email for another Google account.
Your use case is why I bought my own domain name. My wife and I create shared aliases we can both send from. It’s made spousal ensuing with schools so much easier, etc.
I used to get email for an org that had a similar domain as me (they had an extra letter in the middle). Thankfully, not a very big org, I would just bounce addresses that got a lot of misdirected email and I think they shut down and that really solved the problem.
Still annoying, but not as bad as gmail. I just got an email, in Italian, about someone adding a passkey to their ebay account. No way to tell ebay it's not their address / it's not my account.
Similar boat (~25 years) and, while I've run into some sites/services that rejected my domain, I'm pretty sure it's happened fewer than 5 times, total.
YES! I have no idea if we're related, but imagine the surprise when you "first get internet at home", and my father and I decided to search our surname on Altavista, and we found foosball tables and tournaments!
Neither of our names can be confused with a last name and yet I had multiple people writing to it incorrectly, including: as the email attached to a Diners credit card (I called Diners and they asked me what's the right one and "if I don't know the right one how do I know that it's wrong"), as the email for a school 400 km from home (another family must have had the same idea), once for some lawyer stuff (I then learnt that about 100 people in Italy do have my wife's name as a very uncommon last name), and lately as the recovery email for another Google account.