Could it be 100k? Nope, aside from some fundamental change to college pricing (like an asteroid striking the planet) to go from 60 to 100 over 18 years would require an annual rate of increase less than 3%.
If the annual rate of increase is closer to 10%... oof, let's just say you're looking at a 7 figure cost for all 4 years.
all-in total cost of attendance baseline is $74,424 for 2019-20
meaning a freshman entering 18 years from now will pay $1 million if annual inflation is 6.4%
At 3% inflation I'm calculating $128k