The problem with lightweight AR is that with current technology, it's not that useful. If you've ever tried Google Glass or Focals by North, there's not much you can do with them that couldn't be done better with a smartwatch [1].
And if you try to pack a larger FOV display or more processing power into the glasses, you end up with something like HoloLens, and then you've got a similar problem to the VR headsets -- it's probably not something that you'll want to wear for long periods of time (you can't anyway due to battery life), and certainly not something you'd wear walking down the street.
It's not that these are missed opportunities. On the contrary, there are a lot of people who have been working on them for years with billions of dollars spent in the process. But they're hard, and it will take time to get there.
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[1] The one exception was being able to capture quick moments with the Glass camera -- but of course, that raised privacy concerns.
This is part of why I find Facebook's Quest so compelling.
I had much better luck getting people to try things like Daydream, which have extremely limited processing power but could do cartoony graphics just fine.
I think the industry really missed an opportunity to start with lightweight AR. Let the users walk around by showing them where they are and overlay things on top. There are plenty of useful applications; many require precision sensing that phones don't have, but there are others that can be done with just an accelerometer and a camera.