Licenses aren't enforced by most hippie coders due to lack of interest and money. But they sometimes are enforced by greedy big corporations without an interest in anything but lots of money.
https://sfconservancy.org/copyleft-compliance/ https://sfconservancy.org/copyleft-compliance/principles.htm... https://sfconservancy.org/copyleft-compliance/firmware-liber...
https://sfconservancy.org/copyleft-compliance/enforcement-st... https://sfconservancy.org/copyleft-compliance/firmware-liber...
Personally I think the principles they operate under (including extending GPLv3 termination to GPLv2) are fairly reasonable, I don't think unintentional/short-term violations should be punished harshly. I definitely agree that companies that refuse to come into compliance need more incentives to change their behaviour.
https://sfconservancy.org/copyleft-compliance/principles.htm...