Well…just to provide a balanced picture, I remember hearing CBN on radio and later TV in the 1970s. Back then the only religion broadcast was Sunday morning services, and a rare, isolated Billy Graham purchased airtime special.
Bishop Sheen was off the air, and the secular networks themselves were not producing anything Christianity friendly anymore. Catholics talk about Sheen, but remember he got on in the 1950s only because a major secular network put him on. That would no longer happen by the 1970s.
Robertson actually put together a “network”. Not every show, or every function, would have to be self supporting. For example, in my city CBN owned a radio station; the radio station had a call in function, with “counseling” center. They sponsored occasional local services. They operated other radio stations, and rented time on still other radio stations. They developed college operations, a Christian legal defense fund, and outreach services to the poor, and other things.
The 700 club TV show showcased some important Catholic developments in the early years, such as the Catholic Charismatic Renewal, as well as very negative secular developments that would impact on all Christians; but Catholics learned about them here and sometimes nowhere else.
Granted the very real flaws, including nepotism, the weakness of non denominationalism, and much else, still Robertson deserves much credit. People underestimate how great an achievement he did pioneer.