(My last meta question wasn't well received so I will try to be really clear.)

This question How to transcribe Indian classical music using Western music notation? ...is clearly a request for a transcription and should be closed according to the site guidelines.

I don't want to close the question, because simply saying "no transcription requests allowed" seems unhelpful.

One reason I can see for not allowing any transcription request is concern over a copyright violation. Are there other reasons?

To me it would seem friendlier to point the questioner to some explanation of why transcription requests are not allowed.