Showing the music notation to the student = tell
Playing the music to the student = show
Letting the student play the music = engage
Makes sense to me
Showing the music notation to the student = tell
Playing the music to the student = show
Letting the student play the music = engage
Makes sense to me
Playing for them, sure. But you can play once and invite them to play. Not keeping showing until you think they learned.
Internal martial arts has the same warning. Across pretty much all disciplines in the field, the message is that you can only learn these skills kinesthetically. Not talking, not seeing, but feeling instructor corrections with your own body.
But, if we accept a less restrictive/strict outcome, then unguided exploration is very likely a net positive. I think many well known "unorthodox" musicians did this, and also attributed it to exactly that. Though I cannot recall specific examples. So take it with a grain of salt. I'll look up who I suspect.
Edit: Searching for examples of largely self taught musicians, there are lots of examples. What this implies, probably varies wildly. So feel free to correct the examples I encountered: Chopin, Hendrix, Schubert, Uematsu, Bowie.