$2m pre-tax in Utah is only $1.17m after federal and state tax. Take another 10% off the top, and Kalani gets ~$1m a year after paying Caesar and God.
You might think "Fine; but he's been doing this at BYU for 5 years. That's at least $5m." And you're right - but what percentage of your take-home have you saved vs spent over the last 5 years? My guess is that most people haven't saved or invested even 1/3 of their take-home. A house, cars, and kids add up quickly.
Then, there's the issue of baseline expectations. Sure, someone could technically survive on ~$800/month in some areas of the country. But if you've been living the lifestyle of a college head coach, you're going to want a retirement that gives you a little more than the bare minimum. It's likely that a "comfortable" retirement for Kalani is going to cost more than it would for you or for me.
Not trying to throw a pity party for anyone who pulls in that kind of money - but it is helpful to remember that people with big salaries aren't automatically "set for life."