Why are balconies no longer common in single family home design?

Maybe it’s different in other parts of the world. I am drom the coastal southern U.S. most homes built here prior to the 60’s have balconies. They gave you a nice place to sit. Usually have a stronger breeze than the first floor. Less bugs to bother you. Helped keep your house cool because less sunlight was let in through the windows.

Aside from cost, why not include it?