After that it’s much easier to move provider again.

Dead simple email that just works. Their webUI is fine, but I almost exclusively use it on iOS or macOS with the default mail app. They also have some other features (calendar, office suite, video calls) that I don't use. I really like the option to create up to 25 email aliases.

The other features (files, file sharing, calendar) are also well designed and get out of your way.