The issues are complex only if you wish them to be. On the other hand in my simple mind any art form cannot be apropriated since all are works of the originator's imagination and personal skill. And it may sound crass - but the ultimate judgenment is the "market". If you don't like it don't buy, and vice versa. It has always been thus.

As for the specific issue of FN cultural apropriation - any attempt to stifle such merely serve to feed the self inflicted victim culture industry.