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.
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.
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