I thought it was because education back then focused a lot on Greek and Roman times.
Probably not mutually contradictory.
I mean we were using the Greek and Roman ideas of democracy and a Republic for our politics, architecture often reflects politics, indeed public buildings are, along with coinage, the main way a nation projects and envisions itself. The Greek and Roman ideas of an educated citizenry- all of a piece.
Kind of interesting:
Celebration of classicism: the foundation if Western Civilization. It was also done in painting and composing.