Sorry, but big one off wins get overstated with recruiting. They simply do not matter as much as local battles. BYU and Utah battle less for kids than they used to, but BYU battles LSU even less. And OU and Texas too. And those battles for kids against Utah are huge right now.
That alleged national recruiting bump isn't there from those wins. Not for 1 win.
The thing is, locally BYU did get a bump when Sitake was hired, and beating Utah will do it again with some kids. And the number of 3, 4 and 5* kids in Utah is going up. BYU needs to get more wins there, and beating Utah helps more than beating LSU would, or Texas or OU.
I get it though. beating LSU would be awesome. But losing 7 in a row vs Utah would be a killer in state. And BYU needs it more to get the recruits to win the big games later. Recruiting is always the #1 factor.