As long as you’re very thorough about removing any linked connection from your expired e-mail, you should be OK. That includes all accounts that you registered using this e-mail, as well as all e-mail contacts that you’ve built up using that account.
Wow, are you serious? That’s crazy!
What if I delete everything if I ever let my domain lapse?
In the same time, it is the name of my company, I assume I will keep it forever until I die.
As long as you’re very thorough about removing any linked connection from your expired e-mail, you should be OK. That includes all accounts that you registered using this e-mail, as well as all e-mail contacts that you’ve built up using that account.