Clint's salary was 65k at UM.
https://www.umt.edu/human-resources/payroll/docs/faculty-admin-contract-professionals-fy22-wages.pdf
The average High School Track Coach salary in Montana is $38880 as of May 27, 2022, but the salary range typically falls between $31270 and $52763.
I have no idea what he'll actually get paid at Florence, but even on the high end it looks like a pay decrease, although not as great as one might think. I agree that it's probably more family-related (he has 4 kids as mentioned) and he might care more about coaching/watching his kids than $ for the time-being, although supporting a family of 6 on 53k doesn't sound ideal.