I'd first ask: do people actually prefer the walled garden?
In my opinion, the walled garden has very little impact on the day-to-day experience of most users. Partly, this is because the most popular apps were historically available on iOS first (and perhaps exclusively). More apps gives the impression of more freedom, not less.
This makes the walled garden a non-factor for most people, so purchasing decisions are made based on other qualities: design, hardware, user experience, app selection, familiarity with the platform, brand perception, ecosystem lock-in, etc.
I'd first ask: do people actually prefer the walled garden?
In my opinion, the walled garden has very little impact on the day-to-day experience of most users. Partly, this is because the most popular apps were historically available on iOS first (and perhaps exclusively). More apps gives the impression of more freedom, not less.
This makes the walled garden a non-factor for most people, so purchasing decisions are made based on other qualities: design, hardware, user experience, app selection, familiarity with the platform, brand perception, ecosystem lock-in, etc.