The difference now really is that the tech has been proprietized. The "open source" duramax developers are no longer. The cost of progressing the duramax/allison combo past where it is and where it has been since 2014ish is immense, and not wanting to give the info out for free is understandable. Sure, there are different ways to achieve the same goals, and those can be ironed out without giving up much proprietary info. However, moving the goalpost ahead is another story, in my opinion; and in some cases, I think we took a few steps backwards along the way that haven't been recovered yet.