Absolutely no reason, but they've constructed the roadmap to do it. 8 seasons of .500 or better football since going to D1--A/FBS in 1987.
Absent a change in the culture at UA with respect to football, it won't matter whether they are in FBS, FCS, D2, Pop Warner or CYO. Hopefully, with a commitment to the program, better decision making and community involvement, they can build something that's competitive in the "new world" MAC.