Stereotype? No- it is statistics. You have got to be kidding me. Ask any successful Country music PD and they will tell you the same. When you cater to the less affluent you need large cume. This is nothing new or earth shattering. Classical music normally does not get good ratings but the listeners are usualy the richest and most politically influential people in any town.
This applies to TV as well. Example: CNBC gets lousy ratings. However, the typical viewer is a millionaire.
This is business. Going back to the bigotted example you gave, if only gun-toting thugs listened to a particular station, that station would be low rated and would serve less affluent (less desirable potential customers to advertisers). The playlist would have to be formatted to appeal to a much wider audience in order to serve their advertisers. No brain surgery involved.
Therefore the only portion of your argument that is left is the part that Country is a great format. Yes it is, but it seems pretty clear that programmers do not see it as a viable option for the big apple, which is unfortunate.
Other missing formats:
Dance
Alt. Rock
Punk
Hard Rock - Don't talk to me about 92.3. They are dead to me.
Modern A/C or Adult Rock
Classic Hard Rock
Classic Hip-Hop
AAA
Christian Rock
Christian A/C
Beautiful Music
MOYL
Alt. Country
Classic Country