When your email ends in @gmail.com, @proton.me, or any other third-party
domain, you are a tenant on someone else's property. Your address and long-term
access are governed by policies you don't control.
Providers change terms, suspend accounts, or disappear entirely. When that happens, you don't just lose access to an inbox; you lose an identity embedded in professional networks, personal correspondence, and account logins across the web.
The domain name is the only part of an email address that you need to fully own. Mail hosts can be replaced. Software can be migrated. Providers can change. The domain remains; it is the stable layer around which everything else can move.
The first step to owning your email is understanding domain registrars.