have been using FairEmail and it works really well. I have to admit it is a very verbose client which offers a vers large number of options and settings even as you just want to send an email (there's a popup with how you want to send it) but it has never failed me and has a very good support for updates and guide for setting it up. It's free but if you like it I highly recommend to support the developer who is fully committed to it (not personally related to the project in any way).
I would be very upset if this project were to die and I had to find another client.
I don't have an apple computer, but the Asahi Linux project has made me consider it. I'm amazed by all the reverse engineering stuff they've done.
Asahi Linux is a project and community with the goal of porting Linux to Apple Silicon Macs, starting with the 2020 M1 Mac Mini, MacBook Air, and MacBook Pro.