Obviously money talks, but college football players that are taking in serious NIL are thinking of the next step in their journey (the NFL) and so they want to join a program that will highlight their talents and prepare them for the next level. That means a program needs more than just money. A successful coach, a brand that will draw eyeballs, a history of successfully placing players in the pros, and quality of life while in the program are also part of the equation. Nebraska had all of that, minus quality of life, in the 80's and 90's and, to a lesser extent, during a partially resurgent Bo Pelini era, but a program's success from 25 years ago won't weigh very heavily in this equation.
I do get that a team like Nebraska could have success by significantly outbidding other teams through NIL to overcome the other factors, but no team out there has an endless supply of NIL money and if the last 25 years are any indication, Nebraska's ceiling is not particularly high as a member of the B1G.