Not general marketing emails, rather loosely targeted phishing or pointless spam email (one liners which I am not sure what point they serve other than nuisance) from leaked email addresses.
The benefit of having a custom domain is that I provide distinct email aliases to each website, which I keep track of, so I know which website leaked an address (and I also see those email aliases in the failed login attempts to my mail servers).
That also allows me to severe my relationship with a website if they start spamming me, so that may also create a selection bias since I am unaffected by the sort of spam resulting from the same email address being leaked to data brokers and used for marketing, because I delete the alias at the first offense. So I get mostly hit by websites that got hacked.
The benefit of having a custom domain is that I provide distinct email aliases to each website, which I keep track of, so I know which website leaked an address (and I also see those email aliases in the failed login attempts to my mail servers).
That also allows me to severe my relationship with a website if they start spamming me, so that may also create a selection bias since I am unaffected by the sort of spam resulting from the same email address being leaked to data brokers and used for marketing, because I delete the alias at the first offense. So I get mostly hit by websites that got hacked.