I mean people won't like the idea but that's not my point; what you describe variety in superficial traits while maintaining common traits
Applied to humans; skin color, eyes, dwarfism, hypertrichosis... can still interbreed
When it comes to categorization and taxonomy in leaky abstractions like languages the boundaries get a bit hand wavy and usually land on whatever fits the prevailing social desirability bias of the day
The same selection pressures that produced the variety of "superficial" traits also act on "non-superficial" traits - nature does not recognize this distinction.
I mean people won't like the idea but that's not my point; what you describe variety in superficial traits while maintaining common traits
Applied to humans; skin color, eyes, dwarfism, hypertrichosis... can still interbreed
When it comes to categorization and taxonomy in leaky abstractions like languages the boundaries get a bit hand wavy and usually land on whatever fits the prevailing social desirability bias of the day