I moved over to Fastmail a maybe five years ago and it was pretty painless. The actual mechanics I did in an hour or so while half watching a movie.
The hardest bit, which you just have to do slowly over the course of 2-6 months is update your new email in services and accounts (banks, insurance, airlines, etc) but with a password manager, you just do it as you use them and it’s pretty easy.
The best thing for me was that I’ve had my Gmail for 20+ years, so thinning out the list of companies that have my email is nice - now my Gmail is mostly marketing emails from companies I don’t care about. I go into it occasionally to see if there is anything I need and then just delete in bulk.
The hardest bit, which you just have to do slowly over the course of 2-6 months is update your new email in services and accounts (banks, insurance, airlines, etc) but with a password manager, you just do it as you use them and it’s pretty easy.
The best thing for me was that I’ve had my Gmail for 20+ years, so thinning out the list of companies that have my email is nice - now my Gmail is mostly marketing emails from companies I don’t care about. I go into it occasionally to see if there is anything I need and then just delete in bulk.