I host my own mailserver, and to be honest it’s pretty painless. Usually I just let it run without giving it any thought. It’s on rare occasions that I need to put a bit of work into improving the inbound spam scanning.
Selfhosting does need quite some knowledge of the software stack and several additional protocols to set them up correctly to get your outgoing email delivered. Also, like already mentioned in another comment, you absolutely need an IP address from a non-blacklisted subnet (I think most VPS providers will be okay, residential definitely not).
My software stack: Arch Linux (soon NixOS), Postfix, Dovecot, rspamd, opendkim, opendmarc.
Additional techniques configured: SPF, DKIM, DMARC, DNSSEC.
As you can see it’s quite a lot, and I’ve been doing for more than 20 years now, so my opinion can be a bit skewed. I’d say go for it if selfhosting is a hobby.
I am very happy with my Skagen Jorn gen 6 hybrid. Hybrid means both e-ink screen and physical watch hands. It has a few health sensors, can display notifications, track workouts, send commands to Alexa if you want that, and much more. It’s simply an awesome smartwatch in a classic inconspicuous design, and it has a hopping 5 weeks battery life, and it’s supported by Gadgetbridge. Nothing can beat it in my opinion.