I think the big issue here is that there isn't a real obvious next step for tech to take now. VR/AR is great in concept, but it doesn't bring the same level of increase in lifestyle that the iPhone did. We already have all the information at our finger tips wherever we go, this just overlays it with real world instead of looking at a screen we pull out of our pocket at any time. Phones were already an established market too, iPhone just took a huge leap in that established market.
I think the core of the issue here is that companies always need new ideas, but there are only so many uses for things, early advancements will be a much greater leap than later advancements because most of the benefit of new tech is had early on in it's development cycle. Computing as a whole is now to the point that for the vast majority of people, there is no need to advance anymore. I'm not saying there aren't avenues for further advancement, just that for the average person newer advancements don't bring as much new benefit to convince people to change with it. Personally, I don't want an AR headset at all. I'm getting to the point now where I want to disconnect more as the connected world has become too corporate with everything trying to shove ads in your face all the time to sell you ever more crap you don't need. This whole AR push feels more like the next step in that corporate progression more than something the average consumer would truly benefit from so my interest is pretty low due to that (in the AR market as a whole, not just Apple's potential offering).