And that last assumption is truly the hard part. There is no software meritocracy. There is no "if you build it, they will come". It's sales all the way down. Until this changes, whatever is outputted from FAANG/MS market research firms will be what's popular, end of story.
For starters, the separation of the world into "power users" and "normal users" is, to me, a sign of flawed thinking. The goal of a personal computing system should be to allow a complete novice to onramp into a "power user" as their understanding of the system grows. Discoverability and consistency are absolutely key to this and Linux DEs have always been terrible at both (and other Desktops are getting worse too). There are many more problems I could go on about, like walled gardens like Apple's App store or Linux's package repos creating another boundary between users and creators that need not exist, for example.
Point being, separating the audience into "people who get shit, like me" and "people who just want X" is an excuse for having a bad system. Instead of admitting and attempting to address the issue, you instead get to say "well, normal users don't need that and power users should be able to deal with the bullshit".
Even taking the one concrete example you provided in this thread, Apple's App Store is incredibly popular -- in fact in the US it has a 56% marketshare [1] -- so why would a Linux OS moving toward what you prefer would increase adaption? I really see no actual evidence of this; as in the example you give is literally the most popular way to do it. That said, I don't even think it matters either way. I've grown cynical enough by now to realize that humans are a lot more complicated, markets more monopolistic, and purchasing habits are better explained by market researchers than developers (or even HCI researchers!)
[1] https://gs.statcounter.com/os-market-share/mobile/united-sta...
If any one person could do it, it'd have been Linus but he doesn't seem interested. It isn't anything a single individual can deal with because it's part of the community culture.
> Even taking the one concrete example you provided in this thread, Apple's App Store is incredibly popular -- in fact in the US it has a 56% marketshare [1] -- so why would a Linux OS moving toward what you prefer would increase adaption?
It's just one aspect of the problem. Apple's App Store has one thing going for it that Linux doesn't: there is one App Store. You get your application onto the App Store and everyone can use it. This is not true of Linux Repos. Besides which, the number you quoted is for mobile, not a desktop operating system.
Linux Desktop culture has this rhetoric of freedom and control, while simultaneously pushing an application distribution model that wants to manage everything in a very limited way. You can't install applications onto other disks, you can't have two versions of the same application (unless the maintainers have deemed it a worthy use case), and you can't keep old versions of applications around unless you want to keep your whole system back too.