I wonder how they got rid of the sonic boom. My guess is it’s still there, just not very loud.
Back in the 80’s sonic booms would cause head crashes in the Hard Disk Drives of the day.
A local claimed that sonic booms were killing his chickens
The change (increase) in atmospheric density with lower altitude causes the shock wave to refract upward, thus it never reaches the ground.
This is a result of the specific speed and altitude at which the shock wave is formed.
The aircraft sounds like this as it breaks the sound barrier: shhhhshush