One argument that I think deserves extra scrutiny is the idea that extra app stores can be “optional”. The reality is that developers would have a strong incentive to go to the most permissive App Store, and users will follow. Users will also underestimate or ignore risks. You can dismiss that by saying it’s the user’s responsibility, but I think that’s just an abdication of good systems design. I’m not saying that A…
The reality is that your scenario never happened. Not on Android, not on Windows, not on Linux distributions... The 'official' App Store always wins, unless its demands are so onerous a small minority uses a small store in addition to it.
And linux package managers aren't app stores. They're mostly meant for system libraries and core applications, although some devs do distribute their (free) apps through it. In any case, Linux is a weird one to include in this comparison, and I'm pretty sure Steam is still the number one store for getting games on Linux too.
But whatever, another thing: a big part of the reason that the official app store won on Android is because of the lengths Google goes to to scare users from installing apps from "unknown sources", hiding the option to do so, displaying scary popups, etc. That's one of the reasons Epic is suing Google for.