Cignetti's team is filled with 22 year olds. Sure they may have been 3 stars when they graduated from High School but then add 3-4 years of college football experience. Do stars really matter at that point?
Plus ND relies on unproven kids who may not live up to their star rankings where IU already knows what they have before the kid arrives in Bloomington. IU is playing by different rules right now because they had nothing to lose. They could experiment with entirely giving up recruiting HS kids to see what happened. If it failed, then IU would be no worse for wear. ND/OSU/Bama, et al can't afford that type of risk.
The rest of college football will catch up and Cignetti will be just another good coach, not some next-level genius.
Edit: just looked up Mendoza’s HS ranking. He was a three star recruit. Now he’s a Heisman trophy winner. So according to star rankings he would have been less talented than NDs backup QB.