In other words, every individual has the legal go-ahead to find or create blueprints and produce the firearms in their own home (needless to say, these guns do not have serial numbers and are not registered with the federal government), and seemingly the government will do nothing to stop this.

Nope, don't interpret it to mean that, this ruling means you can disseminate files on how to make guns not that anyone can make any gun. This is no different from a book on gunsmithing, anyone can of course possess a book on gunsmithing, even a felon or a child. This does not change the rules on making guns. Before and after 3d printing it is perfectly legal to make your own guns provided you are legally allowed to possess whatever gun you make. So if you are allowed to possess a shotgun then you can make a shotgun, you are not allowed to sell that shotgun without a federal permit. If you were to 3d print or just make from black steel pipe a short barrel or sawed off shotgun without obtaining the proper tax stamp to possess such a weapon you would be committing a federal crime.

people like Cody Wilson should not have to go to court to secure their rights.

He does these things intentionally to go to court to set just these sorts of precedents so that would ruin his whole life's work. He never meant the liberator to be a real gun, just to test the limits of what a gun is under the law and free speech.