80-90 allowed many "new" stations. I don't know what percentage of these station were financially successful but they most likely sliced the "revenue pie" a little thinner for the existing stations. Urban Legion has a quote that the goal was to make radio stations as common as "gas station's" where if one closes it's no big deal.
The company I was managing bought an AM/FM in Lake City, FL, as a trial for mainland expansion. We were making a good return on investment in a little market with one other AM and just our FM and one FM from a nearby town. Docket 80-90 tripled the number of local signals on FM, and we ended up with no profit and having to cut our three local news blocks (two hours in the morning along with national net news and features, an hour at noon and an hour at 5 PM) out entirely and automate everything for satellite programming.
We heard the same story from many other smaller market broadcasters at the state association meeting.
And we had an AM and FM in Tallahasse... the FM was the originating station for the Seminoles sports network but we got as many new and moved FMs as there had been when we bought it. While we remained #1 in the book, we were prevented from raising rates and had to fight the cheap new competitors for every buy.
There are many different views on consolation and clusters but IMHO somehow the economics and cost cutting that have resulted in over leveraged operators has turned many music stations into jukeboxes that opens them up to completion from lower cost streamers. I get radio is a business but it is in the entertainment business. We have forgotten the entertainment part of the equation. It seems most of the creativity comes from the web, not radio.
There is one fact... most people under 40 don't want "personality jocks". They don't want "friends on the radio". They have lots of friends on social media, and they chat with them incessantly. On radio, it is "shut up and play only songs I like".
Wall Street got involved. There is a large number of investors who only look a quarter or two ahead. I never was a fan of Clear Channel but what Bain did to them was wrong.
Bain wanted out of the deal when the recession hit. The courts forced them to close, and they hated it. So they decided to minimize the losses by cutting expenses rather than investing in the product.
I did some thinking and after Audacy gets out on Bankruptcy, the leveraging has to be taken out of radio. A FCC license should never be used as collateral for a loan. I think if an operator goes bankrupt, they either sell the station in one year or turn the license into the FCC.
There are so many cases of stations going into bankruptcy that I can't possibly count them. Since the later 50's, half of all stations have not been profitable. Many if not most bankruptcies are the kind that allows reorganization and negotiation of outstanding debts. Some recover, some don't and are sold. The ones that sell see the proceeds mostly going to the creditors and most of the capital is lost.
And there are cases where stations were profitable but the "big mill in town" closes and suddenly you have a mini-depression and nobody advertises. Or the FCC license a couple of new stations, as they did under Docket 80-90 and nobody makes any money. It is not always the operator's fault, and the FCC correctly lets market forces decide who keeps or sells a station.