>A
What we are about is dictated in part by our politics.
but not in full.

Else you can riddle me please how i like Turn Based combat and Monster Races translates in any way to my worldview.
People are more complicated than that.
Im interrested in History and the development of Human nations.

but on your actual point. Yes, it is important for me. it breaks immersion.
But i have an actual argument here. it doesnt break immersion bcause it goes agaisnt my interrest. The argument that it makes no sense that a Human population that appears to be very seditary and not very well mixed in universe appears heavily racially mixed.

It doesnt break your immersion, but it only does so because you dont care about it. Which is fine, you dont have to care about it but its still a valid argument.

>B
Wrong.
We had this debate in Kingdom Come deliverence and Witcher.
Sometimes a Cigar is just a Cigar. And sometimes medieval Bohemia was ethnically homogenous (by american standards of race anyway, not by actual variance in "socially constructed" ethnicity)

>Rabbit Holes
Im not a Rabbit, but i can deal.
It is not social construction to attribute Characteristics to phenotype. It would be ridiculous to act as if there arent characteristics associated with developing phenotypical characteristics based on enviroment, sexual selection and ressources.
Sickle Cell Anemia is probably one of the best ways to illustrate this , but somehow id be very surprised if you didnt know this already.

But before i go on here, i like to point out that you brought up "Characteristics" beyond looks. Nobody else did. The argument was that Enviroment tends to dictate phenotype, not any particular characteristics.

Lumping everyone with the epicanthic eye fold seems to be stupid because, form what i understand, it could be paralell evolution of a trait.
Meanwhile lumping groups together that share history, ancstry and other traits... yeah i personally dont see why you would not do that.
We do it for any other group of animal.
We also do it for culture, not just culture, we do it for political movements, we do it for philosophical schools and for Art movements.

Why is Human Phenotype the only "thing", as in "thing we are putting a name on" that we wouldnt apply that logic to?