It's a sound stage themed building. The event being staged in that sound stage is Villain Con. Did you think they were going to build a replica of the Orange County Convention Center?
It's perfectly serviceable, just like the original attraction on the other side of the pathway. Universal Studios has a studio theme overall, and that lends itself to varying degrees of "behind the scenes"/"Production sets" views. It's not supposed to be immersive theming just like a real studio.