I didn't mean to suggest that was your concern; I just meant that I am focused on the user experience.
The App Store has not increased the price of mobile apps. Instead, developers argue that the App Store has artificially depressed the cost of mobile apps. Before the App Store, the price to users of mobile software was significantly higher.
I repeat that the choice for side loading is not to offer choice to end-users, but the choice to developers on where and how they want to distribute their app. End users will only have more options if most developers offer their apps on multiple app marketplaces. History suggests, however, that the opposite will happen; there will be App Stores designed around exclusive titles. For example, the user will not have more choice if Instagram has to be downloaded exclusively from a Meta App Store than solely from Apple's App Store.
Apple may indeed be greedy and lazy, but that does not negate that the App Store has been successful primarily because of Apple's single-store model and policies and not despite it! Changes to the App Store model will have unforeseen consequences; time will tell how much those changes negatively affect the marketplace's success.