[giancarlostoro]

Same for self-hosted mail...

[mrweasel]

I haven't tried it, so it might be more complicated than the documentation leads me to believe, but Mox looks promising: https://www.xmox.nl/

[yogorenapan]

I've been using it for a year now. Can vouch for the quality and reliability

[immibis]

I use Postfix and Dovecot. Configuration was annoying, but doable. If you read mail on the server itself then you don't need Dovecot.

[eschaton]

Proxmox has a mail appliance.