I don't love recruiting class rank. A class that would be 25 in one year might be 45 the next, just depending on how recruits are distributed to various teams. BYU beating Utah by 14 spots in 2003 could be less difference than Utah beating BYU by 9 in 2006. And that's ignoring that larger classes score better. So if you have more transfers leaving (and more scholarships to give), then you look like you recruit better.
Instead, lets look at average recruit ranking by year. And because recruit rankings have inflated with time, let's compare it to a baseline of the 1000th best recruit in the class.
Starting from 2002, BYU and Utah were pretty close. It wasn't that BYU was clearly ahead or behind. But with 2010 Utah jumped ahead and the gap has only widened since then.