They aren't wrong on that, though. Skyscrapers spend a large portion of their time empty, and require massive resources to maintain which means large areas of land on the edge of the city or further are dedicated to the resources necessary to maintain such an edifice. Lower buildings have a much lower maintanence cost and footprint, and high density planning allows for the fitting of extremely vibrant and productive city scapes without breaking 5 stories. See pre-war Dresden, Prague or Paris as an example. The Skyscraper doesn't actually accomplish much more than urban-sponge designs do. Some of them are very impressive though.