Well, on Linux, BSD it's a different world, but it works fine for non-commercial stuff.We can all agree that all desktop\laptop app store rather it's Mac ,linux, or Windows PC sucks ass...
On Windows, I use the MS Store for smaller MS own stuff like Netflix App, Powertoys, etc.
Games I get from GOG, Epic and Steam Stores.
On the Mac I also just get smaller stuff and Apples own stuff from the Mac AppStore.
The important tools I need to work, I bought, download and install from the Devs website, they can also auto update, works like a charm.
They even hands me over the control "when to update", I don't like enforced software changes when working of a project. I want to be able to roll back too, this is not possible with Apples AppStore.
So will be iOS AppStore in the future, it's inevitable, third-party AppStores and sideloading will come for sure.
Competition is one of the core things that drives the economies worldwide, that's why antitrust laws exist everywhere.
Then apple will be forced to innovate their ass.