The last thing the industry wants is another Doom (1993). A game that is (now) open source, highly portable, highly moddable, and still FUN and approachable 30 years later (and well preserved, as a result). At the time, it made sense for Id to release the source, because it held their competitors feet to the fire. Today, there is nothing left to innovate on the technology side of video games. They want everything to work like Madden/FIFA, where the publishers do the work a couple modders can pull off in a week and charge full price for it all over again.