I'll buy that the idea of shoes may have spread in the mentioned 14,000 interval (40,000 - 26,000 BCE). But I can't buy the notion that the necessity to wear shoes due to evolutionary changes in human anatomy happened world wide in that period.
Ah, but it wasn't an evolutionary change, according to the article. The lesser toes on shoe-wearers are weaker because they aren't exercised as much, and this shows up in the anatomy.