I pay the electric company to have a store where only approved toasters and microwaves are sold so as to keep quality high!
I pay my car company to ensure that only approved tires, windows, audio, windshield wiper fluid can be used.
This logic is not working.
Apple, and ABC corp, and any other companies can have app stores.
If you want to shop at the 'absurdly high standards store' that's totally fine, but otherwise it's anti-competitive.
There's no reason 'Person A' can't send an app to 'Person B' if they want.
It works on Mac, Windows, Android, Linux and everywhere else.