Again, I ask, what do you save? What is that cost benefit?
Administration overhead. Not having two of everything: 2 history departments, 2 business schools, 2 nursing colleges and on and on and on. Not to mention that you don't have needless competition and empire building between two schools that are nine miles apart.
Akron and Toledo should have never been absorbed into the state system as independent universities. Rhodes did it because he had the populist notion of a four year state university within fifty miles of every Ohioan. Millett (his Regents Chair and a former Fiami Prez) wanted it because he felt that more schools offering more grad/research programs would cut off OSU at the knees and allow Miami to distinguish itself.
All in all, it was horrible public policy. At the same time, California was building the global gold standard of a state university system that was both high quality and affordable by doing the exact opposite: making things highly structured and regulated and forcing schools to stay in their lane, eliminate empire building and internal competition.