I have watched enough to know that there is one issue that spans multiple regimes and thousands of players and it's that there is a serious psychological/emotional demon in that locker room. If things do not start well, and the game is 14-7, it's over. It is not coaching or talent, it is a passed on trait from past to current players. This is also a program where playing football is just not fun. Big moments are just too heavy and too draining with this psyche.
This program is the only one that is constantly pressed against its glorious past where guys cannot play freely or just enjoy it. Instead, every game is the "shoe drop game" and I now understand why Rhule gets swirly about "fighting for Nebraska". His players struggle to fight for themselves because they too believe in the doubts. I think they went into that game insecure and once Indiana scored, they succumbed to it. They didn't quit but they didn't have confidence.
Are there issues like development, play design, play calls, etc? Yes. But this team struggles to remain competitive if things don't go their way early and that's on the players.