> Yes. I can prove that this is real
There's also at least two alternative explanations.
I also get a lot of emails to an account I own from someone who keeps using my email instead of theirs. You'd think they would have noticed they aren't receiving them by now, but apparently not. Are you also totally sure that it's not just someone else entering an email address they don't own for work and party invites?
And for a second explanation, are you sure it wasn't hacked/stolen?
There's groups of people out there that bruteforce and then sell OG accounts, such as short twitter handles and common firstname.lastname email accounts.
The fact that the forwarding rules are still setup and working actually leads me to think it's more likely someone else stole the account rather than that it was deleted and recreated, assuming someone else really has access to it.
There's other possible ways your account could have been compromised too, like having a backup email address for it on some other email provider or domain that did go under or get compromised, but a weak password or a re-used password from a leak seem most likely for the compromise route.
Do you have evidence somehow that the account wasn't stole in that way?