They claimed that man could not fly faster than the speed of sound. A wall existed that would kill any pilot that dared to go there. Then Chuck Yeager showed that their thinking was in fact an illusion, an adjustment of perspective would reveal a practical approach to achieve supersonic.
For now supersonic flight produces sonic booms and requires so much power that fuel consumption is horrendous. Only the military can afford to fly supersonic, and then only sprints between mid-air refueling points. Many claim the shock wave will always accompany aircraft travel faster than the speed of sound in an undisturbed atmosphere; but, who says we can’t tinker with the very air itself?
Richard Lugg has a vision of producing a turbine-electric hybrid propulsion system which has an ability to generate tens of millions of watts of electric power. With that power available, there are various ways to modify the properties of the atmosphere directly ahead of an aircraft, which then allows manipulating the atmosphere to disperse any shock front and concurrently reduce drag. Fuel aboard would then suffice for long journeys at multi-mach speed.
https://www.globalsecurity.org/military/systems/aircraft/hypermach.htm
https://patents.justia.com/inventor/richard-h-lugg
The lore of past was not physics based. If you can show through mathematics and physics how you would change the very physics you are governed by, then there is an argument to be made. While we certainly don’t know everything, not even by a long shot, there are some established physics. And physically, you can’t break the sound barrier without creating the shock wave that defines it. Exception, fly in space where the speed of sound is essentially undefined.