There's another part of Apple's announcement that may help explain. Apple touts this release as "completely rewritten". Rewriting a complex app often results in

There's another part of Apple's announcement that may help explain. Apple touts this release as "completely rewritten". Rewriting a complex app often results in a loss of functionality for no better reason than that things are institutionally forgotten. Invisible UX features like page dragging, keyboard shortcuts, etc. seem especially prone to omission by oversight.