broadcast live. Even playoff games were nearly all broadcast on tape delay after the late local news. Magic Johnson and Larry Bird seriously elevated the profile of the NBA. Then Jordan took it to a new level again.
In 1979, as I recall, most people were hesitant to go "all in" on the Jazz because they were basically a last place team. I remember watching Lakers games on tape delay before the Jazz came to town because Utah was considered part of the Lakers TV market area.
The NBA was well below baseball and football when it came to fan interest. Of course, the 80s changed that.