I have not read the book yet but I intend to do so soon. I have listened to public interactions on You Tube. One potential issue I find is the theory about migration from SE Asia into NE India, and the theory that Australesian Languages like Munda had originated in SE Asia and then came into India by migration. This could have actually happened in reverse direction. It is counterintuitive that Munda language came to Jharkhand from Vietnam, and not the other way round. He should check the Genome project and such other major genetic studies. Notbonly SE Asia but East Asia and Tibbet root populations started out in East and NE India and then migrated out farther east. Logically, so
me of that outflow then went farther to Mongolia, Siberia and into North America. One only needs to understand the on-ground racial reality of Arunachsl Pradesh to realize this.
Theere may have been more recent migrations like the Naga into India but that is not the trend.