I dunno what you guys are doing that makes your nextcloud die without touching it. Mine runs happily until I decide to update it, and that usually goes fine, too. I don't use docker for it, tho.
I swear every update ends up breaking it and putting it into maintenance mode for me. This would then lead to 1-2 hours of going through previously visited links to try and figure out what fixed it previously. For me personally, it seems like it's usually mariadb requiring a manual update that fixes it but it's always a little scary.
I always run occ upgrade and occ db:add-missing-indices after a package upgrade, just to be sure that I do not miss any database migrations. Using Archlinux I wrote a pacman hook so that it happens automatically.
I've been reading nextcloud forums/reddit/lemmy/etc. for years now, and i feel like 90% of the problems are from people using docker or whatever easy one-click solution is out there
I've been running NC the old fashioned way for years now and i've never had problems of NC dying for no reason.
Have i had issues? Of course.... Not not like the ones people keep coming here and shitting on NC
The only times i've had major issues and it was actually a problem with nextcloud, is buggy major version releases... So i never install a new major release until X.0.1 these days. Havent really had problems since