> Oh, they also claim that they have "the world's largest community-driven public library of Adafruit products, including footprints, symbols, datasheets, and simulation models"². I wonder whether they designed these themselves or whether they use existing ones. Could not easily find licenses info.

Their PCB designs are mostly CC Attribution-ShareAlike typically.

What's funny is that most Adafruit products aren't exactly secret. Most of them have open source schematics and PCB layouts. Even when they aren't, they pretty much just a reference design from a data sheet. The kind of people that have the competence to be using board design software could replicate their designs pretty easily.