git clone x.git & cd x & make
Have you tried hardware? The welds are bad, the capacitors are leaks, the leds are in the wrong direction, the transistor are not available, ...Same for chemistry. Sometimes the details are not easy to reproduce. Are the reactives pure enough? How do you mix them without increasing the temperature too much? Fumes? Contamination? How do you separate the solid part and clean it? Even with a foolproof recipe, it's a lot of work to get something useful.
Yes, therefore the solution would be to let everyone to keep reinventing the wheel?
Put differently, there's a big difference between being able to make one of something once and establishing supply chains for scalable industrialized production and distribution resilient against economic and availability changes. If we didn't have more than one way to make wheels from scratch, one day we might wake up to find we no longer have a way to make them at all.