I want an argument about how often I am seeing people being offended by having their preferences criticized. I can take somebody disagreeing with me (except on this issue, of course :) ), and civil society relies on criticism, and people accepting criticism. Berating people because they are dismissive of things they don't like is a path that lies madness. Feedback should not be purely positive, truncating the negative, because then effects that are polarizing or simply have costly disadvantages outcompete effects that do are more mildly positive, but without (or fewer) drawbacks.
Saying that rap is not music may be criticism. But it is certainly ignorant and unconstructive criticism. It is criticism in the same sense that "your mom" jokes are.