Pretty much all aircraft you have to do something if you are stalling.
Some types the over speed limit is linked to some test requirement eg alot of turboprops are limited by the windshield bird strike test. You can go another 50-100knts faster before you will have issues with either structural failure or the prop tips going supersonic. If this is the case there isn't alot of issues with the aircraft overspeeding by 5-10knts.
Other aircraft have a limit due to the airflow over the wing going supersonic once over a certain airspeed once this happens it changes the performance of the wing and is to be avoided.
Now as you increase altitude your Indicated airspeed decreases but so does your maximum speed because as the temperature decreases so does the speed of sound.
You can get to the point where the stall speed is the same as the maximum speed. We call this coffin corner and are trained to avoid it.
I am not a swept wing jet pilot myself which the coffin corner mainly effects so my description may be a bit out. My TP is limited by its wind screens and its pretty well known that the airframe is good for another 50knts over the max we are allowed to fly.