Human predation is a highly plausible contributory factor to the demise of the mammoths..
But it could also be possible that human contact lead to partial taming of these magnificent beasts.
Little tribal girls might have gone out of control styling the mammoths long wooly hair into all sorts curls, plaits, buns, pigtails, ect...
Fussing about so much with ribbons and flowers and dyes,
that these noble creatures eventually lost the will to exist and perished in sheer shame.....???