"Save", "Discard" (or "Don't save"), and "Cancel", where "Cancel" does not dismiss the editor.
(This is the three-button close prompt that's been the standard in desktop operating systems since at least the Windows 3.1 era, but I guess we have to rediscover these things when the same problems come up on mobile.)
That pattern makes more sense when you are A. Editing a document, as opposed to filling out an ephemeral form; and B. The document does not auto-save. This pattern is more likely on desktop, which is where you're getting the correlation from. It's unnecessarily complicated when filling out something that appears in a modal like the article is referring to, e.g. a calendar event.
(This is the three-button close prompt that's been the standard in desktop operating systems since at least the Windows 3.1 era, but I guess we have to rediscover these things when the same problems come up on mobile.)