I would probably recommend two things: 1. Move away from Gmail as soon as possible, to a service like Fastmail or Proton Mail; 2. Have an email from that provider as the “last resort”, i.e. [email protected], while using your domain name based emails for most other things.

This doesn’t solve the “everything is in one basket” issue, but you don’t hear stories of these email providers just “closing” an account and causing immense trouble for the person, at least in part because they have actual support.