Pretty amazing that materials science (lighter, carbon-fiber aircraft; hotter, more efficient/powerful turbines) has made this economic. Concorde never was. NYC-LON seems like the one market where this enables something fundamentally new (well, Concorde did); single-day business trips between two major business centers which were otherwise a full day apart. Transpacific flights would be nice, too, but cutting an alre…
I do think there is a need and market for faster than sound air travel. We have the technology to even minimize the sonic booms for over land travel.
Still, it would take an enormous amount of capital to get a new company up and running. I would love to see an innovated tesla-like company in the aerospace industry though. It's badly needed, IMO.