From a book I'm reading called "Art of the Baga: A Drama of Cultural Reinvention" by Frederick Lamp (1996): "during the colonial occupation by the French, the demand for African art objects in France nearly denuded the Baga cultural landscape of old masks and ritual sculpture." (Page 19) One can see why: Baga masks in particular are remarkable, as this African Art dealer's website illustrates. But to "denude" a cultural landscape -- what an accomplishment.
Yet there is a saving feature of this situation: in real life, there's always a day after, and in the Baga's day after there has evidently been something of a renaissance of traditional practices, in which, the author writes, "[s]ince 1985, my photo albums have exposed [Baga] carvers to works of art now in private and museum collections in other parts of the world."(Page 22.) So it's possible to hope that the Baga themselves will replenish their cultural landscape, and that they may at the same time find a way to deliver new art to admiring outsiders that will escape the demand for authenticity that seems to require stripping people of their own culture.