I'm thinking this over, and I believe the typical lyrics of both rap and country concern the following.
Automobiles and excess details about them.
Substance abuse, generally presented in a celebratory tone.
Guns, and the use there of.
Objectification of women and complaints about how crazy they are.
Running from the law.
Serving time in jail.
Overblown, petty, honor culture type disputes.
Am I wrong, did that not basically cover all the lyrics in both genres? Any suggestions for what I'm missing?
Of course I'm talking about mainstream pop rap and country. I'm sure there are some odd artists here and there who write compelling lyrics for the genres.