I'm not going to argue whether this is true or not, it undoubtedly is, but I'm not sure how this specifically redounds onto Universal Studios Beijing when those economic conditions are just as true in Shanghai, yet they get 14 million visitors a year and are aggressively expanding. I think it's just as simple as the fact that Universal Studios Beijing and/or the surrounding area is just not as exciting a draw as Shanghai Disneyland.
Yes everything has changed or undergone change from ten years ago, but you could literally say that about multiple aspects of life in every country around the world (unless your Bhutan or something).
Out of curiosity, is there railway access to the USB? I've did some cursory research, and it seems like Shanghai Disney has a direct connection to the airport, whereas there's some transferring involved for USB. Wonder if that effects the desirability of travel in any way.