It's also possible their interpretation is shaped by a desire to promote social justice and anti-racism, and oppose harmful stereotypes, taking precedence over strict scientific consistency. This is understandable, and ethical; I'd do the same thing if I thought scientific claims could cause harm. Differentiating humans into biologically distinct groups has contributed to scientific racism and genocides in the last century.

This sort of motivation is not unknown in the social sciences: http://www.rci.rutgers.edu/~jussim/unbearable%20accuracy%20o...