>>213763984
It happens still alot. But the 60s - 80s were the worst years in terms of archtictural preservation. It was much worse back then.

Nowadays you study engineering in a way to preserve old pieces like these. It's common to build old looking buildings from scratch in most cities. Old architecture simply looked better and is more livible. It has a psychological effect on humans.

Pic related is build from scratch. In the 60s this was a parking place.