Apple made it perfectly clear that iDevices would be a walled garden when they released the SDK for third party applications.
That’s retconning at its best - there was no support for 3rd party apps then, just websites.
That's the point, in the beginning there were not supposed to be native apps, just web apps, some of them advertised in Apple site but not otherwise privileged.
The point is that customers who bought an iDevice knew in advance that they were buying into a walled garden ecosystem with a web browser.
It was Google that lied to the public about Android being an "open" ecosystem that allowed you to do anything you liked without interference.