It's a lot of money, but the cost is only going to go up the longer they delay the work. You can't ask the fan base to sit in seats designed and constructed in 1964 when they can sit at home and see every game from multiple angles in high definition. Back then, if you wanted to see the game in real time, you almost always had to buy a ticket.
Northwestern demolished their old stadium and reconstructed. It was in horrible shape. Nebraska isn't in that condition but there are things that have to go, like the horse trough urinals and the bleacher seats designed for skinny 1964 butts.
I was thinking this would take us down to maybe 60,000 seats... it will still be at 80,000 and those red-clad folks will be much more comfortable.