And as an engineer I bet it can be a very satisfying environmemt to work in with less compromises for legacy and economic reasons.
But the problem with long flights today is not the time on the flight which would make supersonic travel worth it.
The real work should be put into optimizing the slowest step of my journey instead. Like being stuck in traffic to and from airport, the time it takes at the airport for security and to get passengers onboard, taxing to runway for 20 minutes, and waiting in queue of airplanes for take-off slot.
Also even in business class or first class there is horrible noise that makes me super-tired and I am expected to mostly just sit around and feel that free booze will make up for the lousy environment.
Give me an onboard gym, showers, less noise, proper air onboard, proper sleep compartments suitable for people being 2m tall and where I can shut myself in and not be disturbed by other pax or crew.
Maybe if this were something I was doing all the time but as a sometimes event, comfortable sleeping and entertainment options (which I can mostly handle by myself at this point) work pretty well.
(Yes, you can find cheaper flight but that's a pretty typical airfare on a major carrier today.)
> For example, in 1997, the round-trip ticket price from New York to London was $7,995 ($12.5 thousand in 2018 dollars), more than 30 times the cost of the cheapest option to fly this route.
I just did a search for this route in January in first class for comparison and saw various options mostly starting around $6000 (round trip), which is similar to your estimate. I'm sure there are reasons people would often pay more to fly that route in first class.