I am not at all certain that TV ever had a “”Golden Age.” In 1961 FCC Chairman Newton Minow declared TV to be “a vast wasteland.” I have seen nothing to convince me he was wrong.
There are some television series that are true masterworks of art.
The Sopranos is one—others include Breaking Bad, The Wire, The Shield.
They operate at the level of entertainment while having the complexity of classic literature for those who have the knowledge to appreciate all the meaning that is there.
That said—the vast majority of TV is total garbage.