This Vox piece talks about "Golden Age"s of TV, in connection with the ending of Mad Men. It seems the first Golden Age was the 1950's. The referent is to the "high culture" approach, live drama and things like Leonard Bernstein's programming explaining classical music.
I more vividly remember JFK's FCC chair, Newton Minow, deploring the "vast wasteland" of TV.
Two takes on one history.