Humans could never have
Humans could never have migrated from Africa into harsher regions (AKA colder areas like Northern Europe/Asia, North America, etc.) without some sort of footwear. That footwear wasn't cushioned, thick heeled, etc, but it did provide a modicum of protection from conditions that the human foot wasn't capable of enduring. Just as the wheel as a tool enabled the advancement of human civilization, footwear enabled humans to move beyond our origins and explore new climates and regions. As we are all now spread throughout the globe, including places where asphalt becomes too hot, or snow/ice are too cold, or even extreme trail running where the terrain is walkable but not runable without shoes, we cannot completely abandon minimal footwear. 2 in foam or "shox" or any of the over engineered and harmful designs of modern shoes are definitely overkill, but there are instances where either a thin layer between the foot and ground or snow and foot are necessary. The most primitive of cultures, at least those living in environments that are not always temperate, use some sort of footwear, be it mocassins or "sandal" type footwear, not to aid the foot but enable it.