I see the points on both sides, to a degree, but when I see a DJ, I think what advantages he may have.
1. He probably has most any tune and knows how to keep things moving.
2. More than likely, he can talk it up and provide all kinds of scratch noises and effects.
He is good as an entertainer that can provide music for any occasion.

OOH
Maybe it is wishful thinking, but I think people appreciates the talent it takes to play an instrument in a creative sense. I think it takes more talent than putting on a disk and dancing around, at least I would. I know, that is a bit sarcastic.