There are certainly lots of motivations for coaching. One is to remain in the game, when you see the end of your playing career approaching. If money was one of those motivations for Smitty...he is making it. Lots of money. Is more always better? There are some that say yes, and there are some that consider other motivations as well.
I would seriously doubt that Jonathan Smith saw making as much money as possible, as the main motivation for his choice to go into coaching. Personally, I was too small to succeed in sports, and I became a musician. I have had lots of motivations to raise my game as a player. To become rich was never one of them.
I don't think it will necessarily be that simple though. I just checked what the MWC football head coach salaries were. This was from 2022:
1. Colorado State's Jay Norvell, $1.6 million
2. Wyoming's Craig Bohl, $1.6 million
3. UNLV's Marcus Arroyo, $1.55 million
4t. Fresno State's Jeff Tedford, $1.5 million
4t. San Jose State's Brent Brennan, $1.5 million
6. Boise State's Andy Avalos, $1.475 million
7. San Diego State's Brady Hoke, $1.1 million
8. Utah State's Blake Anderson, $1.025 million
9. Nevada's Ken Wilson, $950,000
10. New Mexico's Danny Gonzales, $700,000
11. Hawaii's Timmy Chang, $500,010
now, these salaries are in line with the MWC media payout of 4-5M/year per school
Smith, on the other hand, is on a deal that will pay him more than 5M/year. Now, that runs thru 2028 so there would be no rush for Smith to jump ship. At the same time if that's the reality OSU is facing, Smith will know that and he's only 44. And I'd think the differential will be even more glaring for assistant coaches. If OSU is having trouble retaining good assistants at the same time they are recruiting for a MWC level team, and having trouble keeping their good players with the transfer portal dynamics, the Beavs are going to struggle
Smith may or may not have ultimate loyalty to OSU, but his assistants won't, and the players will be aware of better NIL opportunities elsewhere
Maybe the Beavs and Cougs will make it into the Big-12 but that seems a real long shot right now