One of the main reasons the US banned supersonic flights overland is that the only plane capable of them wasn't American. The ban came only after Boeing abandoned their plans for a competitor.
It's rather more a consequence of the very bad handling by the FAA of the sonic booms campaign over Oklahoma City in 1964, and subsequent bad PR associated with supersonic aircraft.
You ignore the fact that sonic booms are really fucking annoying, so I will dispute your claim and say that there is no way to put lipstick on this pig and say it was mishandled by the FAA. The booms annoyed everyone. This issue is further compounded by the fact that there is no useful purpose served by supersonic passenger flight; it causes little inconvenience for a small benefit to a infinitesimal fraction of the population when done over water, it cause an ongoing inconvenience to a large group for that same small gain for a tiny group of wealthy people when done over land.
Don't care. No one is banning supersonic travel, just supersonic travel over land. If it can't be made to work economically over the long oceanic routes then it is a dumb idea that deserves to die. Again. If it works over water then it can stay there.
if it can't be made to work economically then there is no need for regulation to explicitly ban it. That is like saying 'nuclear fusion can't be made to work economically, so lets introduce regulation to ban it.'
That is just an incredibly mindbogglingly stupid way to handle regulation in this sector.
If anything regulate the SOUND being produced and how loud or often they can be.
In fact, with the coming revolution in electric aviation, we could actually have super sonic over land travel. A possible solution beyond the airframe for the BOOM problem is to fly higher and in lower density air.
But if you start flat out with regulation that makes any such innovation incredibly difficult and risky its unlikely people are gone invest in such innovation.
And with electric flight its exactly the case that it would be overland, as it would start out with shorter routes and not cross Atlantic flights. Thus this regulation literally kill possible investment in such architecture.
You're right that the booms annoyed everyone; but the end result is that all supersonic aircraft have been banned, even those that would make less noise than a regular passenger plane.
Boom claims that they can reduce the sonic boom considerably; If the project is sucessful, I believe the ban for overland supersonic flights would change to be based on noise level, rather than aircraft speed.
https://en.wikipedia.org/wiki/Oklahoma_City_sonic_boom_tests