> Just because a company folds doesn't mean they can violate licensing agreements.

It does if that's the law. Every jurisdiction routinely overrules contracts as unenforceable on the basis of some overriding law, so it wouldn't even really be that unusual. Whether it's a good idea or not is another question and one that depends almost entirely on second, third and higher order effects.

There probably is a world where all software is libre software and we still see similar rates of development, but it's not at all clear how you could get there. Especially not if you cared about the damage caused by upending the business models of a significant fraction of the world economy.

Nah. No jurisdiction is going to violate the IP rights of a separate company just because one of their customers or partners is forced to liquidate.