That is my point - the necessary material science in many respects is just a knowledge. If you have copper it is relatively easy to make copper wire, at least some crude one, if you know what it is for. It took 2000 years to build the knowledge, yet having that knowledge one can rebuild a lot of stuff in orders of magnitude shorter timeframe. Btw, that reminded about that book that i liked a lot back then as a child https://en.wikipedia.org/wiki/The_Mysterious_Island - rebuilding a significant pieces of civilization starting from scratch almost.