How can you say that something that already exists is a technically impossible dream? There are already tens of millions of consumer VR headsets out there (and I'm not including phone VR).I have quite a few friends who work in the AR/VR space, and they tell me that it is more of a technically impossible dream than a reality. The tech that exists is not wowing anyone, and what people want is not even remotely viable. The technology is simply not there, and it won't be for decades. I sincerely doubt that Apple will release a headset of any kind in the next 10 years. Computer processing power would need to be at least 50 times more powerful than anything that currently exists. That is not going to happen any time soon.
It "wows" most people who try it, in my experience. The issue is longer term retention.
Current processing power is fine—though more power is always better, of course. I think comfort and optics are much bigger issues, and those are hard problems to solve. Everyone had a different face shape, and many people wear glasses, and glasses aren't really compatible with thin and light headsets with a wide field of view.
I am less bullish on see-through AR, though. I don't think the technology is there for wide FOV AR in a reasonably compact package that people would be willing to wear all day even while out in public.