The closer we get to release, the more I worry that their decision to make this a backwards-compatible revision that also has its own entire set of rules changes, subclasses, magic items, monsters, and adventures is going to leave everyone unhappy.
They know players will be unhappy if they have to throw away their books.
So instead they'll change everything so that you just won't want to open them. And if you do open them, you also need to open the revised rules in the new books, too.
I'm with you here. Compatability with adventures (monsters, loot) I find good. Classes and player facing rules not so. I mean what if you take a 5e character that uses a 5e rule for something to a One table where the rule that the 5e build depends is altered. Or just a class feature? Imagine the confusion if a feature that does the same thematic thing have the same name in both? What about mixing features from both editions?