They do maintain compatibility, it's just obviously running in compatibility mode because of hardware changes. If your app doesn't account for a notched displa

They do maintain compatibility, it's just obviously running in compatibility mode because of hardware changes. If your app doesn't account for a notched display, or a retina screen, or multi-tasking or whatever, then there's nothing Apple can do aside from run it as it used to run on older hardware, without supporting the new features.