I agree with your market analysis. Private jets are often referred to as "time machines" given how much time HNW / exec travelers can save. There's a market segment that's willing to pay a high premium for reduced travel time.
Separately, I wonder if a lot of the demand is also obviated by in-air wifi.
Yes. Most companies won't even spring for business/first class, which is 10-20% the cost of a charter. Unless your time is both limited and worth 4 digits per hour, it's not worth it.