Yes, it's sad that Canonical is pushing Snap before those kinks are ironed out. In general it's a solid distro for people not familiar with Linux, but having to stumble over those issues is a dealbreaker.

Linux being easier than Windows is true in some ways, but it completely sidesteps issues Windows and macOS solved for a while, e.g. forcing users to upgrade. It's annoying but some people just... don't do the bare minimum. E.g. a friend's dad has been using Linux for probably a decade by now, and for some reason apt auto upgrades broke (likely powerloss during upgrade). An image based OS like Fedora Atomic doesn't have this issue, as it won't apply updates to the running OS (by default).

I don't have Subnautica but it is on my wishlist because you can play in VR, which is what I mostly play these days. PCVR is not as reliable on Linux as standard games, but nevertheless more than 50% of titles do work flawlessly now. Subnautica is definitely one of them - you should check for other people who've got your problem on ProtonDB. If you actually care, look into it more, you should be able to get all of those games running.