Tutu was a 2nd rounder and GM's miss on them all the time.
OT Robinson was the 2nd pick in the entire draft and it looks like Tutu is at least an NFL player.
Who's to say if they didn't pick Tutu that they would have picked Humphrey? 2nd round busts are about a 50/50 and Tutu could end up on the right side of the 50 if he has a good year.
Perhaps there is some recency bias? Think back to Robinson or Austin the 8th pick in the draft. They were on teams desperate for talent and had many chances to succeed. Tutu been on a deep team and will only really get a chance to play regularly this year.