The Linux Kernel ABI is incredibly stable, thanks to Linus, it's only the userland built up around it by other people that doesn't give a damn about compatibility. This isn't a significant issue for other OSs because they have a well defined base system and care about compatibility (because users care about compatibility).
I'm not entirely sure why you are being downvoted. The statements may not be entirely true and a bit volatile, but it's been my experience to a large extent. One of the things I like about docker, flatpak, etc. is that it allows for entire apps and dependencies to be encapsulated together. Less interruption and down time fixing things.
When I use Linux as my main OS, I lose about a day or so every other month to dealing with upgrade/update fallout. It's discouraging to say the least. With Windows, it's been about every other year, and macOS every major version gives me a little grief for something. Both far less frequent than any Linux distro I've used.
Don't get me wrong, I do enjoy using linux, that said, I still have very weak trust of it as my primary desktop/laptop OS. I use all three regularly.
> When I use Linux as my main OS, I lose about a day or so every other month to dealing with upgrade/update fallout.
One of the big benefits of Linux is you have control over this by picking your distribution. If you used, for example, Debian you wouldn't have this problem as updates don't break things. If, on the other hand, you don't mind dealing with the occasional update issue and want bleeding edge packages then something like Arch might be better.
But choosing a distro that doesn't update gives you other problems. Flatpak allows for a more hybrid approach where you get up to date software but a stable base. (Plus you can rollback software if those updates lead to problems)
Yes. I wasn't arguing against Flatpak, just the impression that Linux was unstable. Personally I'm very much looking forward to Flatpak or Snap taking off... I run Debian stable on my main system and there are always a few packages I have to personally backport.
I'm not saying it can't be stable.. but by your own statement there's packages you have to backport yourself at times. There's a pull between current and stable, and Linux distros in general don't do as good a job as macOS or Windows on that imho. Doesn't mean I don't use it, just pointing out the flaws that cause me pain.