Well written article, and being that I am of both Celtic and Indigenous heritage I can agree with most of what you've shared here. There's a website that clears up quite a bit in lieu of "plastic shamanism" - http://www.newagefraud.org/about.html

As someone who has done genealogical research, and still continues to search out my own roots, I suggest to you to not take anything at face value when determining someone else's heritage however, rather fact check and get to know the person before making assumptions. Listen to the stories others have to share, and let your own knowledge, intuition and wisdom be your guide in discernment.