Who is this bozo? NPR isn't the least bit "successful" in any free market sense of the word: it would collapse as quickly as Air America were it not subsidized by the government.
You're avoiding a very important point, however. Mr. Derbyshire notes that two of the top three radio shows are on NPR, each with listenership comparable to that of Rush Limbaugh's.
By the size of the audience, NPR is obviously quite successful -- and I would suggest to you that NPR's political influence is much greater than Mr. Limbaugh's.
The advantage NPR has with "Morning Edition" and "All Things Considered" is that they've got access to a wide array of very intelligent folks who have many different points of view, and who are capable of expressing their views in depth. I generally don't agree with what those folks say, but their intellectual abilities are quite evident.
By contrast, conservative talk radio is based on a format where one man expresses his opinions for three hours. Mr. Limbaugh or Mr. Hannity or whomever -- no matter how bright they may be -- is still only one man whose daily task is to be the Oracle. All knowledge depends on what they've scanned through the night before -- and I find that when they speak on topics with which I'm very familiar, they're quite often shallow or even incorrect, because it's clear that they don't have a deep grasp of the topic.
Limbaugh 14M listeners outlandishly successful, NPR 13M listeners an abject failure. Yeh that’s the ticket.