There isn't user choice, only developer choice. For example, if I want to play Fortnite with my IRL friends I must download Epic Launcher. If I want to play WoW with my friends I must download BattleNet, if I want to play Counter Strike I must download Steam. I don't get much choice in what my already existing community of friends decides to play. This is likely to be mirrored in phone app stores. Need whatsapp/facebook/instagram on your phone? download the Meta Store! Don't like their T&C? Pound sand.