People already can and do choose Apple knowing that they are entering a walled garden.
Apple has made a strategic decision to maintain this walled garden. This decision is one of the company’s key differentiators.
Your position appears to be “I want to force Apple to abandon a key market differentiator in service of a marginal gain in personal freedom for a marginal segment of customers who would actually care about such change.”
Apple customers are lacking choice in software just as much as Trader Joe’s customers are lacking choice in food brands.
Is the walled garden a key differentiator? When most people buy a phone, I think they're usually thinking about the camera and screen, or the security and privacy features. (And note the sandboxing features are part of the phone, not part of the app store.) I'd love to see data on this if you can find any.
I certainly didn't buy an iphone because I want to pay an extra tax whenever I buy apps.
Apple has made a strategic decision to maintain this walled garden. This decision is one of the company’s key differentiators.
Your position appears to be “I want to force Apple to abandon a key market differentiator in service of a marginal gain in personal freedom for a marginal segment of customers who would actually care about such change.”
Apple customers are lacking choice in software just as much as Trader Joe’s customers are lacking choice in food brands.