Register your own domain, use a third-party provider to handle actual sending and receiving (I use proton, which makes the setup very easy), forward your Gmail to your personal domain address and as renewals and reminders come in switch your email on services to your personal domain.

After a year or two losing Gmail becomes an inconvenience; after a few more years it is nothing. As everything is now on your own domain name you can switch providers without affecting anything.

That's what I did about 5 years ago and my only regret is not doing it earlier.