I used to run various PC based home theatre bits of software, but they're all inevitably a pain to manage, don't work right, and require fiddling.

Got the Shield TV pro 2019(?) version, pointed Plex at my NAS, and it plays content flawlessly. Youtube, Amazon Prime, Netflix all work well too.

In theory it also plays games - but Nvidia's game service isn't launched here in Australia, and I've not found a game on the Google Play store that's isn't outright terrible. Steam Link theoretically works, but none of the games in my Steam library are suited to play with a controller. Theoretically there's emulators for various consoles which I've seen people saying is excellent, but I've never been able to make any of them work.

Like just about any modern device - it does need to be rebooted occasionally, but for the most part it's just turn on and go.