Panmixia (funny term) is something that has always existed. You don't have the colour of skin that you have because from the begining of times on cluster of white people decided to not mix with others, evolution and mixing leaded to your phenotypia. So I thing you are confusing terms to get your point.

The value is not in maintaining whatever kimera you made about race, the value is to maintain humanity that is the hability to understand between all humans and to be empathic... Well, probably you disagree with me