Inhospitable

Something is coming together in my mind.  Flamenco is not popular music. Vocally, it is described from outside as "inhospitable," not prone to popularization. Flamenco guitar is considered pleasurable, almost as background music. Baile is the most touristic aspect, and the toque (guitar playing) is used as accompaniment to the dance.

But the cante has never been popular, unless transformed into other genres of music like the copla. The harsh-sounding voices, the melisma, the difficulty of comprehending the lyrics, or, for the non-Spanish speaker, their utter impenetrability. Hence it seems that cante is the terrain of the purists, because most non-flamenco type people do not even like it in the first place.  

The cante has always been literary in some sense, too. In the sense of attracting literary interest to its lyrics, which have a deep connection to traditional Spanish lyric poetry in the folkloric tradition.

So a vernacular setting of Lorca is not necessarily a popularizing one. Let's call this the "unpopular vernacular." This is a third space opening up, similar to the vernacularizing classical tradition.