That was also my favorite part of that video. How he cuts all of his videos is very well done. And how he doesn't say anything and only demonstrates, it's very effective.
Just imagine the increments of time...years, decades, centuries, or more that likely passed between the individual advances in technique demonstrated...
I don't think it's the act of invention that's the hard part, but without long-distance communication or trade, the same inventions had to be made over, and over, and over again.
If a tribe died out due to disease/war/famine, etc, any advancements they had made were lost.
I'm curious where bow drills fit into this progression? They appear easier to make because you don't need to drill a hole through a rock; you just need a dimpled rock as top bearing. Also, isn't pressing down with a bow drill making more friction so faster fires?
You can even use wood as the top bearing in a bow drill, as long as you lubricate it slightly. It's sufficient to rub it with leaves, or rub your thumb on the side of your nose and then on the bearing. I've gone to primitive survival classes, and gotten fire this way; my first, making all the pieces and learning the technique, took about three days, off and on. My second one with the same rig took five minutes.
With practice they're fast to make. In one class we divided into groups of half a dozen, and competed to get the first bow drill fire without using any pre-made tools. No knives or axes, just whatever rocks we could find. The winners took less than an hour.
Hand drills are a lot more difficult to use, and I've never gotten the hang of it. But I've seen some people get hand drill fires pretty reliably in a couple minutes.
There's nothing primitive about the things demonstrated in his videos. The self-made / nature friendly / survival ratio is high in my view. But I have a passion with old and simple but effective and life critical. Also the importance of geometry, you see how curves and dents will result in sub-optimal energy conversion. I'd love to find videos about gradual precision increasing and scale changes (assembling large and or small things in smart and subtles ways).
Chatting with people on #emacs, I learned that with long weed and time you could craft fat ropes long enough to build rope bridges. That too was fascinating.
There's also a few topic on the web about bootstrapping the tech stack from scratch. Which is a fun thing to imagine too. Which leads to what alternative path could technology take, maybe there's no need to replay history, one could quickly go into ceramics, lenses, metals and rapidly assemble radio emitters, various sensors, and (maybe?) avoid large scale agriculture, oil based devices etc etc
ps: this https://youtu.be/kiHojsMTBeA?t=166 is also pretty smart, how a few cross "sticks" leads to a natural frame for a basket. How to derive structure and strength from weak bits of plants and trees.
https://www.youtube.com/watch?v=RzDMCVdPwnE
I like how he shows the repeated fails and how it take a long time to practice to get better at it.