I have self-hosted E-mail for myself and my family for years, probably close to a decade now--I lost count. It's a learning curve at first but once it's dialed in and working, there's really nothing to touch. Occasionally, like once every two years or so, I find my spam filter process crashed and failed to relaunch or something, causing delivery delays.

"...but once it's dialed in and working, there's really nothing to touch"

...until your upstream changes something.

Or an opaque third party (i.e. a spam list) puts you on their lists.

No, also people who host themselves and enjoy the hobby time and don't understand how the general public lives.

I'm one of those people, generally, but even I'm not signing up to host an email server. Screw that.