The big problem with Concorde was that it wasn't allowed to fly supersonically over most land due to noise restrictions. Thus eg transcontinental US, where the time gain might have been quite attractive, was ruled out. The same issue combined with limited range also ruled out nonstop London-far east (Singapore, Hong Kong, Seoul, Tokyo) or London-West Coast US. Are these issues likely to be any different now?

Also - not sure what you call Mach 1 class but the business jet market has a lot of planes which will cruise at eg Mach 0.93 or so - ie faster than airliners - and speed is valued in that market. If noise issues over land can be navigated successfully then I would expect there is a good market for supersonic business jets.