

Not convenient. My computer is actually a docked Steamdeck I only use occasionally in Desktop mode. I know lots of people will frown at that, but I do 99% of anything I do (aside from gaming), on my phone since a long time ago. For work I have a work laptop and I surely wouldn’t want to store my mails there.
So having Thunderbird on my Steamdeck for browsing old e-mails is just not convenient for me.
My small homeserver is part of a backup strategy, so putting something on it reachable via a webUI of some sort will also ensure all of that is backed up. Since my Steamdeck is mostly games and many saves are stored in the cloud automatically, I don’t back it up as much, not worth the effort.
If I had an e-mail provider I’d be confident staying with for the next few decades, sure. But I don’t feel confident about it and it would just move my problem with old gmail e-mails to the next provider.
And the next provider may not have a “takeout” system. Since Proton has encryption you have to use their client? I remember hearing about Proton bridge to connect to other clients, and it was supposedly clunky.