Comment by plqbfbv

I also examined Tuta (in addition to Proton) as replacement for Gmail, and as others have said for Proton, the big no for me was having to deal with other software components to have IMAP or other access options.

I have integrations e.g. for scripts, external mailers and so on, so I don't want to pay something AND still have to setup something myself and maintain it. Fastmail has the concept of app passwords, which are username+password combos that you can scope to specific services (e.g. only sending emails, only accessing calendar, ...), which is perfect for my needs.