Mannahnin
Scion of Murgen (He/Him)
I agree that "species" has a tendency to prompt silly debates (like the oversimplified myth a lot of us carry around in our heads about the dividing line being whether two creatures can breed, or have fertile offspring).That is the rub - we don't have a non-loaded term for major biological differences, because humans don't have major biological differences.
Race is loaded. Species would be good but creates silly arguments. Speaking for myself, I don't really have a preference beyond not liking either of those.
But for me I think the bigger strike is aesthetic- as a directly Latin-derived word it "feels" scientific and modern. It's a word which fits perfectly in a sci-fi game or fictional work but not as well in fantasy of a quasi-medieval/pre-modern world.
As opposed to People which comes from Middle English, and before that Anglo-Norman, Old French, then back to Latin. Or Folk (Middle English from Old English from proto-West Germanic). Or Kindred (Middle English from Old English).
Words that have been in the language longer feel "older" and more poetic. Words English got directly from Latin and/or more recently almost always sound and feel more modern and scientific.