That retcon can’t even be accurately described as a retcon, since you have fusion generators running on a single fusion core for centuries, still in the game. It’s just a nifty but poorly implemented mechanic that is directly at odds with the world it’s set in. Since the story is set 10 years further forward than any…

The big bump up for the new version of Unity was physically based shaders and lighting to support that...which is pretty much what everyone else is doing now.