You could not be more right on the first part of your statement and more wrong on the second.
isu will never be Iowa's biggest rival. Iowa has achieved and will continue to strive to do the best they can in conference competition first and foremost. This just completed regularly scheduled football season is case in point. Iowa's goals included winning all of their scheduled games and they accomplished that. However, another goal was to be Big Ten champions and while the Hawks fell short on that in the CCG, beating isu has zero bearing. How can a game against your 'biggest' rival have no bearing?
Well, same goes for isu, you say. Well, think about that for just a minute or two. How realistic is it for isu to plan on winning a big xii championship in football? Beating Iowa in football, in many regards, is the extent of hope for isu currently. Perhaps the new coaching staff will realign that thinking, but for now it is why isu fans feel that Iowa just has to be the biggest rival and that that is reciprocated from Iowa fans.