A thought provoking and fun video. The low-tech skills they are practicing are important to certain types of survival situations, such as getting hurt or lost for a few days. As a deer hunter though, I have seen how fast and strong they are. I seriously doubt that a deer would be incapacitated by that deadfall trap. He would probably be more likely to bag a deer with a properly placed wire snare. I hunt grouse (partridge) with my wife. It is possible to walk 10 miles in prime habit and not get a clear shot at a grouse. I even hear it is possible to miss a shot

. The guys sharing the single grouse in the video makes good TV, but that little 3 oz breast is only enough for one person for a day. It is very difficult to replace the calories expended by hunting with the game bagged on that hunt.
Certainly, any owned survival skill increases ones chance of doomsday survival, if for no other reason than being seen to be of value to a tribal group. I guess I'm skeptical that anyone could survive by going solo in the woods. It's not the 17th century anymore, and there are a LOT more people everywhere. Food is very scarce in the woods, and there would, at first, be swarms of foragers. Anyone alone or in a small band who had an accumulation of food or supplies would soon be attacked for it.
Probably, tribal life would be possible along coastlines, but only for a dispersed, and very limited number of people.