Also, there's essentially nothing you can't do with stone given primitive tools, sand, and a shitload of talent/time. One thing about ancient people is that they had all of these in abundance. Making arguments from the position of "they couldn't have done this with the tools they had" is almost always wrong because it's coming from a modern perspective of how tedious and uneconomical it'd be to do it today.
Again, you can do this to shape virtually any rock. Stonemasons don't do this today because it's excessively annoying and slow. It's not a coincidence that khafre enthroned is a royal piece for a wealthy and powerful pharoah.
Most people will have some familiarity with emery cloth/sandpaper, which are basically the same principle. We don't even need to look at fancy egyptian statues. Carnelian beads were a common trade item across the Ancient near east and Egypt made this way. It's not magic.
I think we just don't comprehend, as mentioned above, how much time and effort could be allowed for back then. I'm sure 100 people could create a near perfect vase given 30 years to work on it (random example).
This idea that its just not feasible because it is hard ignores existing architecture that we can date in places like China and India, but cannot easily replicate in the US or other spaces because the generationally developed skill and method is not available.
This precision occurs in hard materials like stone, in massive scale as well as in soft materials like cottons and silks which weren't replicated in Europe in previous or current times.
How absurd! Skill and craftsmanship can get you far, but they will not allow you to craft with such precision that it's imperceivable to the human eye, how could they even verify their efforts? The video, while long, presents dozens of well structured arguments with strong evidence, your dismissal comes off as extremely arrogant and foolish in comparison.
We know there were civilizations in North America such as the Mississippi River valley mound builders - but our knowledge tops out at “they existed”. It would not surprise me if agrarian civilization rose and fell multiple times due to climate change.
We might find some old equipment from an elder spacefaring species. If we don't find anything, maybe we should leave some human monuments out there so the next civilization can know about us.
> The points L1, L2, and L3 are positions of unstable equilibrium. Any object orbiting at L1, L2, or L3 will tend to fall out of orbit; it is therefore rare to find natural objects there, and spacecraft inhabiting these areas must employ a small but critical amount of station keeping in order to maintain their position.
It doesn't take advanced technology to do either of those things.
My favorite one was pi is there in the relationship between the pyramid base length and its height, and the Egyptians had no notion of pi. Again, space aliens! But if the Egyptians used a wheel 1 cubit in diameter to mark out the base, and the height was in cubits, then there's pi.
(What's a cubit?)
Casting iron(copper) is relativly easy and powerful.
Experiment with hot things in fire and you will discover it after a while.
"Why couldn’t they have use some natural form of biodegradable materials?"
Like bones for bows and spears? Humans did that, but metal is apparently more effective and useful.