If AppStore model isn’t needed why is Tinder available on AppStore. They could have gone side load model. But didn’t. This just shows why AppStore is relevant.
"Side loading" is a second class citizen reserved for criminals and nerds.
A true first class distribution model would allow you to install directly from the web without messing with settings. Perhaps even running as WASM seamlessly out of the box, never once switching contexts into a storefront.
If we'd done it this way from the beginning we'd have true cross-platform apps written in WASM with full native experiences. Microsoft still might have their phone, too. But things didn't evolve that way, sadly... Apple and Google wanted their control and walled gardens.
Of course, to reach true parity now we'd have to remove the app store to let web distribution catch up in the minds of consumers. But that will never happen unless we can lobby for antitrust breakups of these titans.