Re: One software manager to rule them all!
If I understand correctly, historically Windows has taken a slightly more MacOS-esq approach of assuming apps will redundantly install various versioned copies of libraries in their local Program Data (or .App) directories - rather than orchestrating shared ones (which bigger Linux distributions have the luxury of being able to coordinate. Would that make this more of an MSI-on-steroids rather than a "traditional package manager"?
Not sure myself yet.
One of the things I dislike about the way it's done on Linux is that it places a heavy emphasis on a distro adopting a piece of OSS software and including it in their repositories. Ok, for the able Penguinista it's perhaps not so difficult to use cmake or, heaven forbid, ./configure to build from source. But it's at that point where you've pretty much lost the un-*nix-savvy user. Even if a software developer chooses to go to all the phaff of maintaining packages for all the myriad different systems out there, it's still beyond the un-*nix-savvy user to add the software developer's repos to their apt, or yum, or dnf, or snap, etc setup.
The duplication of libraries thing: in my view its swings and roundabouts. Just this afternoon I've been needing an older version of the lexxer generator Flex. And, with Ubuntu / apt, finding and installing an older package version is an absolute nuissance. Microsoft's way does at least make this kind of thing totally trivial; you just uninstall the new version (though even that's not totally necessary, it's down to the app and how it manages its install), install the old, et voila you're off and away.
Also, with a large distro-centric package repository there's a need for each and every application within it to be built against the versions of libraries that are chosen for it. This has never been achieved 100%; dig around in some of the more obscure corners of a repo and its generally quite easy to find something that, though all dependencies are claimed to have been met, has been packaged up with the wrong dependencies for that particular version of the app.
Also, I'm just not convinced that storage is, generally speaking, sufficiently scarce to warrant a package management system that strives to ensure that the bare minimum of space is taken up by shared libraries. It's not exactly resulting in a modern full-fat Linux distro being anything less than a few GB installed. With a lot of software these days what takes up space is all the pretty bits - bitmaps and such - and they're generally not shared between applications anyway. Mass market IoT stuff in priinciple benefits on price from efficient use of storage space, but then again how much of that stuff is actually updated ever, anyway?
Anyway, it's sounding like MS have realised that getting rid of application installers ("Use the MS Store") was a bad idea, and is undoing that somewhat. Good.