Not at all DNJ ! An arranger keyboard is actually a musical instrument !! What instrument does a DJ play ? If when you play an arranger keyboard , all you do is push buttons then I fully understand your confusion about what a musician is !! I have heard you play so I am surprised that you would even make the comparison .

But most arranger players actually know how to and actually play chords . Melodies , harmonies and chord progressions that they would do in a straight up keyboard . The arranger simply follows their piano playing . If you switch off the arranger element you can still hear the musician playing . If you switch off the record , backing track or MP3 file what music can you hear from a DJ ? A fist pump makes no sound !!