7 hour to London is actually 10 hours when you factor in the commute to the airport, security, planing, flight, deplaning, shuttle to hotel.

Cutting it to 3.5 hours isn't a 50% overall decrease, because those 3.5 will turn into 6.5 of real time.

So the marginal value of faster flight goes down the shorter the trip is, and these supersonic airplanes can't do the super long Pacific flights because physics.

It's a much smaller niche than is often imagined. But it's still a niche, I guess.