I thought that modern architecture, at least in large buildings, was driven by new, more efficent, cheaper methods of construction, along with the ability to make large glass windows, plus the universality of air conditioning so that windows don't have to open, along with a dearth of Italian artists willing to work for little money and do the art work that decorated the buildings of the Teens through 50's.
The group whose webpage is above apparently influenced Stumpie in today's exec. order that new federal buildings in DC use Greek, Roman, Gothic and a couple I missed architecture. The same group wants to rebuild Pennsyylvania Station in NYC, even though Madison Square Garden is in the way. They have several compalaints about the station including that the trains are sometimes late. How does the design of the building cause that!