Getting away from D&D, PbtA is an example of a system that has given us a multitude of games. It doesn't use the OGL to be open but the idea of open gaming in rpgs grew from the OGL, I believe. So even if the OGL is killed and we no longer have an open D&D environment, open gaming is still with us. Without D&D, it will be much smaller and I am certainly not downplaying the potential loss of livelihood of 3pp but open gaming will not die. And I hope that in the future, WotC/Hasbro learns that their walled garden may be very pretty and tame, but ultimately dull, and people quit paying to walk through the gate.