It's quite possible that this will be answered by people's behavior in practice rather than by philosophizing about it. If FOSS projects develop which include

It's quite possible that this will be answered by people's behavior in practice rather than by philosophizing about it. If FOSS projects develop which include tiny bits from copyrighted pieces of software, and they are not challenged for long enough, and see wide use - then the answer will be effectively "yes". If people steer clear of doing this and ask permission for every little bit used - then that will be the custom, and those who don't might end up in court.