It really takes a staggering level of hubris and incredibly narrow vision to take the position that "ratings data isn't good for any purpose if it isn't used in making a sale". There are other worlds besides yours and other people who use radio and its related information differently than you do. Really.
Ratings companies are businesses. Radio Stations are, for the most part, businesses. The radio business buys ratings so that they can justify pricing to advertisers.
Stations also use ratings as an internal metric for things like staff bonuses, performance evaluations and the like. But if it were not for the sales aspect, we would not pay the high costs that ratings involve. There are much better ways of getting useful programming information.
A "bad book"? Radio's response: "I think we need to do some perceptual research... maybe a new music test, too!" Ratings are not programming research... they are a past-tense autopsy.
For two years, 1973 to 1975, San Juan, PR had no ratings. Advertisers had no way of determining value of ads, so they offered much lower rates than they had been paying. By mid-1975, radio revenue was off by more than half in the market. I spent months talking to the Roslows and recruiting The Pulse and in mid 1975, they began surveying San Juan 4 times a year... by 1976 radio revenue was not only up to the 1971-1972 level, it actually exceeded that point by about 25% by 1976.
I had relaunched two new formats prior to the entry of The Pulse. They came out very well when the first book arrived. We did not make a single programming change because of the ratings. We had our own programming research for that.
And today, there are plenty of stations that don't subscribe to the ratings. Generally, that is because there is no information to be obtained in ratings that help them sell because those are niche stations and ratings only show how few listeners they have. Those stations certainly can't get any useful programming information from the ratings.