I'm guessing Apple is hoping that the apps will be the killer thing. They claim to have not expected the app store to be so successful, so maybe they're hoping they don't need to create the killer app that someone else will. That's why they are introducing the dev tools for it so much sooner than it being available. They are banking on killer apps being announced before launch
I remember a news article about the Apple headset a few weeks before it was officially revealed. It cited anonymous Apple employees being pessimistic about the prospects of the new headset, and one of them was actually quoted as saying that perhaps the apps will save it.
This sounds indeed like Apple doesn't know what it might be good for, while hoping app developers will find some novel use case.
Otherwise it will not be much more than an AR window manger.
In any given group of people something like this will appeal to some and not to others. From the limited about of information that leaked out, it is pretty clear that most people in Apple didn’t really know much about the device and only had rumors. It’s likely that only a few had ever tried to use one.
this is a new general purpose computing device, so most of the regular things you might do with a laptop would be doable here. Of course the difference here is that you have an immersive view and a nearly unlimited screen to work with and one where you can seamlessly blend the virtual and physical world. I think that is going to be transformative for the existing applications and will open up a space for other activities that we haven’t seen yet.