I see that 6...b6 is also advocated in a new ChessBase product by GM Felix Blohberger.

Perhaps they mean introduce to the student, rather than introduce to theory. In the "Introduction by the Author" Krishnater calls it rare rather than new.

I came across this:

"Instead of the standard ...c5 approach that allows favorable liquidation with dxc5, Krishnater introduces the ambitious 6.Be3 b6, preparing ...c5 with improved timing and leading to hybrid KID/Benoni structures that maintain the complexity King's Indian players seek."

This seems interesting to me, but I'm not sure how Krishnater can "introduce" such an old line. (Drazen Marovic advocated it in a repertoire book from 1991, 11 years before Krishnater's birth.)