I don't know if I agree. Sure, there's plenty of garbage stations out there and a lot of transmitters being used for the same format in a market for the sole purpose of helping "pull down" the other station in the market.
However, particularly small transmitters and translators often give the market more choices that would never survive in a market. And in today's age when people are more and more finicky with their music tastes and ability to just stream from their iPods, diversity in formats, IMO, can help radio survive.
Small stations that are simply "simulcasting" or whatever are low cost. So even if they deliver smaller ratings due to a niche, as long as there's enough advertising to support it, why not? It helps keep listeners happy and cross promotions can attract listeners to the other corporate offerings.
I'm not for all these "buffer" stations but there are some benefits to having more radio stations. It's the way the conglomerates use them that counts.
And I know this post won't go over well with folks on these boards who were in the radio biz and cry about local radio vanishing. I can sympathize, but that doesn't change the reality of splintering music tastes and radio's struggle to keep up.