More the removal of the fairness doctrine.
Even if it was left in place it would have become increasingly a joke as non-broadcast news grew in the form of cable rollouts and the internet.
I don't think this gets mentioned enough. Rush Limbaugh was the result of the doctrine's abolition. You can draw a straight line from Limbaugh to Fox News, et al.
WNYC's "One the Media" have done just this:
"How Rush Limbaugh Paved The Way For Trump" (2021)
<https://www.wnycstudios.org/podcasts/otm/episodes/how-rush-l...>
Audio: <https://chrt.fm/track/53A61E/pdst.fm/e/dts.podtrac.com/pts/r...> (MP3)