Yeah, but not one of these folks had a prime time TV show on a popular network like Fox. Of all of the people in prominent media positions, no one did it better than Beck. That is a fact. He reached a lot of folks who would never in a million years come across the people you mentioned. A relative small number of people are political junkies. Yet, even here, there are more than a few who have a vague understanding at best.
For good reason. They were doing their exposés of Communism long before there was a Fox network or even cable television for that matter. People relied on books and magazines for information and to educate themselves.
The writers I mentioned are for the most part major figures in the field. You are likely too young to know anything about them considering that you think what's important is that they weren't on Fox.
What's important is the quality of the information they presented and not how it was presented. And what Beck is presenting is often nonsense. An obvious example being Beck's ridiculous claim that Martin Luther King was some sort of conservative. King had two major advisers on his staff, Stanley Levison and Hunter Pitts O'Dell. They both had been long time members of the Communist Party when Joe Stalin and Nikita Khrushchev were running the show. The presence of Levison and O'Dell is what earned King his FBI wiretaps during the Kennedy administration. But this doesn't fit Beck's clownish version of history so instead of informing his fans of this complicating fact of King's life he'll be doing some sort of MLK reenactment this fall while filling his fan's heads with more of his nonsense.
Alan Ryskind was another excellent writer who I failed to include in my list and he wrote about this aspect of King: