Why someone said flatter maxilla makes your face look more cold and calculating more forward one more warm friendly?

[Pei]

?

 

[Lulleko]

flatter maxilla = asian phenotype = asian stereotype.

 

[Pei]

flatter maxilla = asian phenotype = asian stereotype.

I just made it because someone said red bundy and Richard Ramirez have flatter face making more cold calulate look but Asians are known for being low emotional ?