Yes. But. (This is the general gist of the below posting)
I agree with everything you write.
But is has to be mentioned that the TV/Movie world, a most often complete colormanaged world (don’t quote me on that!) sees this a bit more nuanced. Under standard illumination, melanin falls along one hue line in a vectoscope plot (top view onto YCbCr so that CbCr lie in the xy plane you look at, that hue line goes from zero saturation to saturated in one specific hue angle). Differences in skintone-hue lie close in hue angle to this line. The colors of skin with a lot of blood in it, are rotated in hue-angle and can be discerned on a vectorscope plot. So, under standard illumination, the hues of skintones are rather well definied in the rec.709 colorspace. Everything else you mention, style, creative intent, etc. still comes after that.
To me it is a bit of a mystery why even studio photographers who have the chance to control almost everything to a level that TV/Movies can control, do not care too much for skintones in a well defined colorspace. Sure, retouching and grading will change that skintone to whatever, but checking your calibration (or better the lack therof) with a vectorscope type plot is almost unheard of in the photography world. I don’t know why! Lower production value? Colorchecker calibration good enough for most? Multitude of colorspaces that are too much to handle?
This does not surprise me, if this jpeg-collection comes out of the photography world.
edit1: @afre caught me using wrong words 
now it should be consistent.
addendum: that melanin story is more intricate to how I described it. there are two types of melanin with slightly different color. I am not sure which one the skintone line actually follows or whether it is a split-the-difference situation. the reasoning for that line still holds though, I think.