I agree with the part that they are both past their prime but..
Rock music is technically better music, it involves more skill and better songwrtiting.
Rap music is just a guy rhyming over a looped beat, a child could record a rap song...
To create Rock music it takes sheer talent and musical ability, it even has complicated time signatures and rock vocalists are extremely versatile singers. e.g, Chris Cornell, Mike Patton, Freddie Mercury etc etc....