iPhones didn't solve any "problems", but they unquestionably ushered in a new era in smartphone user interfaces. The public wasn't clamoring for a touchscreen phone, Apple just made one up and told everyone it was the best thing ever. And it was. The touchscreen is, for nearly 99% of uses, just better. In the same vein, you'd have to be pretty bereft of imagination to not see how AR/VR promises an incredibly useful and exciting approach to interfaces.
Instead of staring down at a tiny device or simply wracking your brain in desperation any time you need information about something in the world around you (driving/walking direction, business hours, the history of a sculpture in an art gallery, the name of an acquaintance approaching you down the sidewalk, etc.), imagine that the information is just... there. In the environment with you. That is incredibly useful, and is an incredible way to interact with information. Imagine cooking along to a recipe laid out on the countertop in front of you, with generative AI guiding you through different techniques (or even helping you change a tire on a busy roadside).
Instead of needing bunches of different tiny screens for bunches of different use cases (I wake up and sit at my medium work screen, sometimes scroll my tiny screen, go home and sit on the couch and watch my large screen, maybe over the weekend I'll catch a movie on the extra large screen), you just need a single device that produces exactly the screen and environment you want. That's the promise of VR. I could be on a cramped flight watching a movie on an Imax screen or writing code with 3 separate monitors in front of me.
We could go on and on and on just imagining excited scenarios where AR/VR would provide an incredible way to interact with tech. It all just hinges on how well it can be done. Apple has now laid out the requirements needed for a truly satisfying UX with these devices, so the next step will be to see if the industry can make devices small enough, powerful enough, with enough battery life, etc. to make these viable for the average consumer. If that happens, I predict that in 10 years flat-screen based (TVs, smartphones, desktop PCs, laptops) devices will all but disappear.