The only alternative I can think of is to grow smaller cities. But that's not going to happen as long as people prefer to move to a metropolis and are ready to

The only alternative I can think of is to grow smaller cities. But that's not going to happen as long as people prefer to move to a metropolis and are ready to put up with the cost of living. For the change to start, the option of living in a metropolis should start sucking more than the option of living in a smaller city.