You can have composability just by assets being permissively licensed. For example freesound.org or the various asset stores that are chock full of free stuff a

You can have composability just by assets being permissively licensed. For example freesound.org or the various asset stores that are chock full of free stuff as well as paid things. What I suspect people want is free co-marketing rather than composability. HyperDragons is famous because it did something interesting with CrytoKitties that were already famous. In that case you also need to be very careful using other peoples IP so probably want a license anyway.