I think the huge phone craze will eventually die off, but not in the same way. Phones will be sized more between an SE and iPhone X, but unfold into a small tablet so we have the best of both worlds. I know some recent sci-fi shows (and MS renders, lol) have been depicting things like this, but I've thought this for a long time. Such a device would be able to integrate wirelessly with large displays to run macOS applications through Marzipan with a desktop interface when connected using a future version of Apple's W series chip. They won't replace desktops entirely, but be used a lot when traveling or out in the field instead of bringing a laptop.
The same W series chip protocols could be used to do the heavy lifting for AR powered glasses as well. The glasses would have cameras, 3D range finding, motion sensors, etc—but the graphical and compute power would come from the wireless display link to the device in the pocket. I think eventually Apple wants the Apple Watch to be able to run something like this, but that's quite a way down the road. This helps keep the headset from needing quite as much battery power and keeps it slim so it looks like a regular pair of glasses. Eventually I think AR overlays will make the need for phone and tablet and maybe even desktop connected devices less important as we progress deeper into the 2030s (though they could possibly connect into desktops or cloud computing for more intensive tasks). Anyway, this is just my personal vision of what I think will happen in the future.