Coaches always think they have the next wrinkle they can pull out and it's going to make them successful again. It might be the recruiting class coming in, anticipating roster gains from a year of growth, a change to scheme or whatever it happens to be but I guarantee he thinks he could be successful next year at Iowa State. He's going to want the shot to prove it. He knows he can't get a better job than the one he has.
I guarantee there are plenty of people posting on this message board right now who hate the job they currently have. I also guarantee those same people wouldn't do the same work they're doing for a 50%+ pay cut and change of scenery.
It’s rarely a good idea to compare college coaching jobs to the average job. Or someone that’s only made 100k for 10 years to those that have more built up wealth. But to your question, as long as there wasn’t a non-compete, that confidence you first referenced would result in many taking that 50% and getting another job and improving one’s career, if not pay in the long run. Plus improved happiness and home life in the short run. Once you reach a certain level of wealth, you tend to have much less of an issue spending money on those latter things.
That optimism of a turnaround next year isn’t present in this case. Both sides know it’s over. In some ways, Jamie is lucky to have budget constraints in his pocket.