Ah the old "reverse identity theft".

Relevant xkcd:

https://xkcd.com/1279/

Yeah, I get the same regularly.

Smartly, I got firstnamemiddleinitiallastname@gmail.com. I never get anybody else' details.

On the other hand... Occasionally someone gets my info because some careless person entered my email address into their system incorrectly. You'd think this problem would be solved by moving to a custom domain, but I still once in a while find someone completely ignore what I put into the form and sign me up as firstnamelastname@gmail.com.