Not mainstream, not expected as per Western cultural standards, my guess... As when Debussy infused Eastern tunes into Western mainstream 100+ years ago. Not that easy to define nowadays that we r all mixed and racially-"corrected" but some genetic/racial knowledge tells us what that is.
like for me, Tchaikovsky's 4th under Karajan sounds "exotic": the guy never heard Russian folk tune "the birch in the meadow" so his take is beautiful but "exotic" to my ears.
like for me, Tchaikovsky's 4th under Karajan sounds "exotic": the guy never heard Russian folk tune "the birch in the meadow" so his take is beautiful but "exotic" to my ears.