When I worked as a middle-level Exec in a global corporate, the Co paid for me to travel in J around the world.. I was BA Gold and SQ Gold as I spent a lot of time in Asia.
I would quite like to fly in J nowadays. BUT..............there are other things that I need to do with that limited amount of money that I get as a Pension. So I only fly J when I can find a great deal. I just came back from PEK via HKG in J on a great deal, found by an agent.
A friend from our village always travelled in F. The Corporate for which he worked paid for F for its Exec team without thinking. They also had a long-haul private jet for the CEO.
I don't know anyone who travels a lot who is willing to pay J or F from their own money.