Yeah the Docker version hated me, mainly due to it sometimes getting a bit behind on updates and then having schema mismatches if I ran an update in that missed the previous one. No issues with the Snap thus far
I used to have this problem. I started pulling a version number (like 27) instead of "latest" so that I could just pull minor releases when I did updates, and then I manually step up the version in the docker-config file for major versions when I'm ready for them. (I don't like to pull a major release version until there's been 1 or 2 maintenance releases since my nextcloud is fairly critical for my family)