Well apart from being a miserable old sod generally, I've just heard all this stuff so many times before.
Much as I'd love to see a new SST in a reasonable amount of time, the fact is that Japan is not going to build one.
What they are doing is research so that IF
a new SST project did happen, a multinational effort to be sure, they would bring a lot to this particular 'party'.
As a major lead contractor.
But, on my last bittersweet Concorde flight, OAE's delivery to retirement in BGI
in November 2003, I made a point of looking and filming of the dark sky, curve of the Earth (being a LHR
we made 60,000 ft and conditions were pretty clear), the speed on the cabin displays, because I knew this would almost certainly be my last ever supersonic flight.
And I'm still in my 30's.
Unless someone gives me a ton of cash, getting me on one of those Mig-25 experience flights, or the Rutan sub-orbital vehicle when it enters service, I don't expect to travel faster than sound again.
This is a source of profound regret to me, another aspect of Concorde I so miss, but I consider myself blessed by my time on this aircraft.