Have to say I've never had a single issue with pihole unlike the OP. It's literally been "install and forget" - not a single outage in maybe 3 years of use. When I use the Internet elsewhere I see what a good job it does when I'm at home...
Since then, it's trucked along without issue for years. Couldn't use the internet without it at this point.
Having said that, I have a Pi running HomeBridge to make a Pi camera and some non Apple Homekit capable IoT shit work with my phones/iPad, and I'm pretty sure the last few times it's rebooted were due to power outages, and I can't remember the last time I needed to even hit the HomeBridge web interface, never mind ssh into it. I'm a little surprised unscheduled power outages haven't borked the sd card, it's not even configured to do the ramfs overlay thing.
[1]: https://www.friendlyelec.com/index.php?route=product/product...