Obviously we don't expect you to understand what words actually mean, but clearly Stirtz was not Iowa's entire offense.
I think Stirtz is being both overvalued and undervalued in this discussion. He was the focal point, and he was the main reason they made the elite 8, regardless of his tournament statistics. Him being on the floor in those moments was the most important reason for Iowa advancing IMO. Example - no one that makes that play running to catch the inbound on the Folgers three. You don't lose someone like Stirtz and have it not matter.
However, I don't think this is some major blow to the team with McCollum at the helm. The dude is obviously insanely talented at evaluating what he can get out of his players. Coleman should fit in nicely and the rest of the team is going to improve as well.