This is a good question.

I think that relative deprivation is a big factor here.

The reason why we would want jets in the first place is the perception that others have them and we don’t.

Maybe if it was easily possible for everyone to have a private jet, the interest in having one would diminish. Or it would be considered weird to not have one (I am often ridiculed for my decision to get rid of my car and use public transport instead due to idealistic reasons) and people for whom being integrated into society and „part of the normal crowd“ would think they need one even if they were flight phobic.