You didn't wait for the crickets ;) There are quite a few free engines on the market that predate the Unity/UE show, and if you've spent any time in the area you know the landscape pretty well. jME, Panda, Torque, Irrlicht, OGRE,....
Your post says "I don't know anything about game development, but I've got this sweet anti-F/OSS rant I've been waiting to post for a while"