It's possible Kalani doesn't want to do that, but pretty much every coach at a USC, Texas, Georgia, Notre Dame etc was once a coach at "lesser" school with less attention, and left to go to the bigger-time program.
If what you're saying is true, then no coach would ever go to those programs...but they do. I don't know Sitake well enough to know if he's the type that would or not, but to flat state that it's a bad situation and nobody would every go to a higher profile job (because of the higher expectations) is demonstrably incorrect.
I'm not saying there's anything to any rumor of Kalani to USC, but I can't see the reason to dismiss it as "well, moving up a level would carry higher expectations that Sitake doesn't want". That's a terrible mentality for a HC to have.