[1] https://www.sciencealert.com/the-close-door-buttons-in-eleva...
Broad generalizations about nations are rarely accurate.
It has to do with the owners of the elevators choosing to override the programming.
Elevator doors are initially programmed to stay open for a period of time based on their capacity, intended use, type of building, etc...
If the owner or installer of the elevator finds this default not suitable for the environment and use, then the wait time can be changed, and/or the door close button function can be altered.
[edit] In some elevators, the reason the door close button doesn't work is because it's not meant to be used by ordinary people on an ordinary day. It's meant for when the elevator is in utility or fire mode, used by maintenance people, firefighters, moving companies, etc...
They push the door open button and the door opens, and stays open while equipment is moved in and out. The door closes when the door close button is pressed.
People assume every button is for them.
Agreed. But I was trying, by giving a counterexample, to respond to an even broader generalization: that "door buttons in elevators don't do anything". And I did say "usually".