I don't think anyone thought we'd have 16K photorealistic high field of view VR....

There are basically two reasons.

1. Expensive R&D
2. Small / Niche market

Companies want to make profits. Most companies are focused on short-term over long-term profits. Not all, but most.

Companies like this likely see VR development as too risky. So the only companies you see investing in the long term are those with leaders who are truly passionate about VR and the future of VR / AR.

Creating expensive products for a very small market is very risky, and a lot of people / companies are not willing to take that risk.