Well that's because AR and VR are strictly worse for most use cases as compared to traditional human computer interfaces.

The mouse, keyboard, and monitor is pretty much just right. Highly productive, you can go super fast, with extreme information density.

VR and AR are obviously much slower to navigate because physical worlds are slow to navigate and that's what they're mimicing. We might assume a 3D world has more information density than a 2D screen... But 90% of the time it doesn't. I don't have eyes on the back of my head. And, usually, I'm going to be staring at a 2D thing.

As I've written before, I can imagine an essentially science-fictional version of AR being potentially interesting. Wear normal looking classes or contacts, look at something, and immediately get information through some subtle communications mechanism to be determined.

VR has basically been for niche high-end gamers. I can imagine a jet flighter simulation might be good for VR but I'm not even sure that's such a thing these days. One can imagine other uses like virtual exploration but it hasn't been that interesting and a big monitor works pretty well as an alternative.