Let me rephrase.
Why wasn't the Concorde a success? And what about this is different?
The Concorde used ancient technology and was never updated due to lack of competition. It was the last airplane to still employ a flight engineer.
Additionally the design was inherently flawed, which led to the AF4590 disaster.
The sonic booms were too loud due to old tech.
The post 9/11 slowdown was the nail in the coffin.
Finally, Mach2 just wasn't fast enough to move the needle. Mach5 is a very different story.