Hello!
You waste on average 2-3 hrs per journey in big airports when flying commercial, but it takes minutes to board private jet via FBO terminals....
You don't waste that much time when you fly business or first class. There are express lanes at check-in and security and whenerver an early check-in is required there will be a lounge for you where you can spend your time working or eating or both.
As others have already written, the typical business jet passenger chooses this type of transport because it will get him from A to B in the morning and onward to C in the evening - or D if the lady at C has made other arrangements but D is still an option...) according to his (flexible!) schedule without the need to coordinate his meeting times with airline schedules. He doesn't care the least whether his flight will cost him 430 Euros or 4300 or 43000. And many of these people do not want to share their plane with strangers for a variety of reasons. And additionally many bizjet customers don't fly between large airports but smaller airfields instead which are closer to their home and destination. Not something a company like this new startup will be able to provide.
But who knows, maybe their concept will get accepted by the market? Who thought ten years ago that something like Facebook would become a success...
Regards
Max