The Japanese population is on decline. So is the population of (young) students. To win the fierce survival race (like in the movie "Battle Royale"), universities in Tokyo are working hard to recruit a decreasing number of high school students nowadays.
Students decide which university to go, of course, mainly based on their hope and dream about their future, but the university location is also important for their decision.
This factor cannot be easily dismissed by saying that such a motivation is not right. Besides acquiring knowledges and skills at university, students need to enjoy their campus life. If you live in a university village isolated by high mountains and it takes hours to reach the downtown Tokyo, the only thing you do is to study. It is easy to guess that such a student can be quite vulnerable at mental stresses and frustrations. If your dream is to become a scholar, this situation might be the best condition. However, not everyone wants to follow that path, for sure.
University administrators know this fact (because they used to be like these modern students 40 years ago?), so that they try hard to refurbish their main campus located in the central part of Tokyo. In 1990s, when Tokyo was in the bubble economy, everyone was so rich that they want to enter universities at any rate. They believed that the graduation from University is a ticket to be rich and happy. So, universities need a gigantic campus, which was impossible to possess in the downtown Tokyo area. Inevitably, the admins started to purchase big lands in the peripheral part of Tokyo, and built new lecture halls there. As a result, by 2001, many universities in Tokyo have at least two campuses: a small one in the downtown and a huge one in the outskirts of Tokyo.
When the bubble bursted and the Japanese society sank deeply in the recession, many people lost their bright dreams and hopes. A serious problem is that many had to give up marriage, or having a baby even if they manage to marry, due to financial reasons. The birth rate dropped and soon the population started to fall.
The huge campuses are no need now. Students can choose where to study now, and they choose the small main campus in the heart of Tokyo. Those universities who shifted the main function to the outskirts campus became suddenly unpopular, so they started to move back again to the center. This is what is happening right now.
