Guess what happens with voters. They vote for their conference. When Utah was the only top 20 team a year ago guess who voted them the highest? Yep, guys from the PAC 12 area. It isn't hard.
No one considers Utah a prestigious football team. They just don't. Google most prestigious college football teams and tell me where Utah ends up. I bet you don't find one with them in the top 50. The reason Utah is ranked high to begin with? Voters feel an obligation to vote for someone in the Pac 12. I doubt it will be top 10.
Colorado has a national title and Heisman winner. They are more prestigious than Utah.
Sorry, but you have a warped sense of where college football values Utah football. It is pretty funny.