A lot of useful manufacturing techniques are simply not public because it is very expensive to discover them, and obviously most entities don't want to share th

A lot of useful manufacturing techniques are simply not public because it is very expensive to discover them, and obviously most entities don't want to share their techniques with other. If anything, non-standard not-well-known techniques have only been popularized recently because software is used so much in hardware design these days that some hardware designers have imbued the ethos of FOSS. Without that I doubt people will share niche techniques like this which have the potential to make lots of money.