Not all of them...

My wife's cousin (and many others) proofs the difference
But then he also sings during his deejaying (not all the time, but only a few songs on an evening)

He used to play in a 2 man duo, playing both keyboards and guitar..
So he understands what he is doing...

And there is many more of his kind of deejays in Holland
But then he is a little bit older then all the youth

He makes a good 2nd income as a wedding deejay
But then he is an entertainer..
Amd i think that exactly catches the essence..
As soon as a deejay realises he is an entertainer..
And starts entertaining people
He will succeed just fine at weddings...