I was in another country when there was a power outage at home. My internet went down, the server restart but couldn't reconnect anymore because the optical network router also had some problems after the power outage. I could ask my folks to restart, and turn on off things but nothing more than that. So I couldn't reach my Nextcloud instance and other stuff. Maybe an uninterruptible power supply could have helped but the more I was thinking about it after just didn't really worth the hassle anymore. Add a UPS okay. But why not add a dual WAN failover router for extra security if the internet goes down again? etc. It's a bottomless pit (like most hobbies tbh)
Also (and that's a me problem maybe) I was using Tailscale but I'm more "paranoid" about it nowadays. Single point of failure service, US-only SSO login (MS, Github, Apple, Google), what if my Apple account gets locked if I redeem a gift card and I can't use Tailscale anymore? I still believe in self hosting but probably I want something even more "self" to the extremes.
Self hosting sounds so simple, but if you consider all the critical factors involved, in becomes a full time job. You own your server. In every regard.
And security is only one crucial aspect. How spam filters react to your IP is another story.
In the end I cherrish the dream but rely on third party server providers.