Most people don't really get out their way to set up backup manually. Either system should try really hard to avoid corruption or implement a recovery system. Ideally both.

Just use libdecor. Client is supposed to manage its content.

Packaging software for linux is an insane problem. All distributions are so similar yet so different, all of these nuisances prevent you from making much assumptions about the host OS which for instance forced flatpak to be basically a generic distro you run apps on. For obvious reasons it's not an ideal situation, memory consumption is bad, performance in various ways is impacted. I believe that the true packaging format will have to cut some corners and be specific by design to smaller set of distributions. Pretty much how snaps are built around Ubuntu, which imo. is a necessary compromise to have something reasonably fast and lightweight.

Also it needs to be mentioned that snap store don't force any styling guidelines where it comes to description of packages. Most apps have names that are not styled properly, have low quality icons etc. This is a deal breaker for me

It helps distributing applications that don't break left and right. Deepin is creating its own thing as well and they said they are gonna check host system first then supplement missing components if needed. This should result in maximum space saving, but allow developers to cherry pick dependencies.

How this is gonna play out remains to be seen.

If I'm being honest, if you can't use deepin distro I wouldnt bother. Remixes are nowhere near in terms of quality

I don't know if sideloading snap apps is a thing, but it has been proven that creating a snap repo isn't particularly difficult. Snap server being closed isn't really an issue Imho.

It's dead. There were some attempts, but without money you can't build a desktop

Actually snap desktop may be alright. I tried Ubuntu core os and the performance isn't so bad

Even if there are Linux preinstalled laptops people don't buy them. Linux on desktop has too many fundamental Issues and still isn't a viable option imo. Even top Linux distributions don't have particularly good interfaces with very questionable design choices.