> With modern technology, you can 3D print whatever you need, generate software, and run advanced manufacturing all in a small workshop just by yourself.
I assure you, you cannot.
Go ahead and make a USB A-B cable from scratch. A 30-year-old product that retails for $2 so hardly 'advanced manufacturing'.
I admit that I'm just blown away by the metalwork in tiny little electrical connectors. To me it's as amazing as watchmaking, if not more so, because the connectors are multiple-nines reliable, dirt cheap, and probably have never been touched by human hands when you receive them.