It is the instrument used in theory classes to explain the system ofharmony, and students in some schools must take courses in “key-board harmony” in which they learn to harmonize simple melodiesby ear
While I agree having chordal instrument facility is unbelievably necessary as a musician, it should be a yes-and situation. Have seen discourse in the last few years that in the jazz/BAM realm drumset is just as important to know as piano given the complex rhythmic theory involved in the music