UNLV has a nice enough stadium that I think they can still get mid level teams like Iowa State, Kansas, Vandy, Virginia Tech, etc.. for home and home games. Also can continue to get teams like Arizona State, UCLA, California, etc.. who really have no legit chance at the college playoffs.
I think you're selling ASU a bit short. That coach is really good.
But to your point if I'm a P4 school I'm not taking any 'risky' road games vs any G6 schools. They need you more than you need them on the resume.
Not saying it won't happen just that there's no reason for any top third in conference type P4 teams to go on the road.