Getting enough teaching staff and laboratory space is expensive and exponentially harder to manage. Plus you will need support such as cheap mass housing. Then

Getting enough teaching staff and laboratory space is expensive and exponentially harder to manage. Plus you will need support such as cheap mass housing. Then on top of that, big mass transport. It's not insurmountable, and quite a lot a chicken and egg problem. The most important part is, what do you do with drop outs? Or with people who try and cannot find fit? How do you handle people who have to quit for personal or family reasons, who suddenly now are concentrated on one place near the university?