Actually, the apparent change in direction is not all that surprising, since the basis of Scott Barry Kaufman's status in research on giftedness is deemphasizing giftedness as a trait (i.e., high native cognitive or other ability), and conceptualizing it more as a state (i.e., conditional, and developed primarily through interaction with environmental forces and what one might call character qualities, such as growth mindset).
The other two authors are notable for writing about underrepresented populations (ethnic minority GT, and marginalized populations in general).
