I use catchall email addresses. If your service is called foobar.com I will register at your place with [email protected]
If I ever receive spam addressed to [email protected] that is unrelated to your service I know you leaked or abused my data. Result: you will get a DSGVO complaint and I filter all emails addressed to this address from my inbox.
The good thing about using a catchall email address is that I don't have to create a mailbox for each service/purpose, I can just make email addresses up as I go. All you need for that is your own domain and a mailserver that aupports it.
If I ever receive spam addressed to [email protected] that is unrelated to your service I know you leaked or abused my data. Result: you will get a DSGVO complaint and I filter all emails addressed to this address from my inbox.
The good thing about using a catchall email address is that I don't have to create a mailbox for each service/purpose, I can just make email addresses up as I go. All you need for that is your own domain and a mailserver that aupports it.