@Coily the snake
From a legal standpoint if the games were open source the only way Hasbro could try to clamp down on them is to sue the original creators for the actions of others to continue it after the cease and desist or to retroactively sue them. In either case it would fly about as well in court as Tom the rock with wings.

It would be nice if the final state and source material of the game was "accidentally leaked" by an anonymous source.