This is a strange statement.
Five of the top ten RBs in yards in Big Ten history are from Wisconsin. That's half of the all time leaders all on one team in the conference. Ron Dayne, Johnathan Taylor, Montee Ball, Melvin Gordon, and Anthony Davis. If you want to talk rushing TDs, add in James White.
At WR, Wisconsin has two receivers with more yards than ANY Ohio State receiver in history- Lee Evans and James Abbrederis. If you want to go yards per reception or TDs instead, Lee Evans stats are almost the same as Devin Smith.
Are these not speed or skilled positions? RB and WR?
For Iowa I might agree with your statement, if you exclude TE. Iowa consistently has good TEs, which is a skill position.
If you were talking defense, then you should know 3 of the top 5 all time leaders in interceptions are from Wisconsin- Jamar Fletcher, Jim Leonhard, and Jeff Messenger. Two of the top ten are from Iowa.
Maybe tackles for loss? Top ten Iowa has Mitch King, Ohio State has Joey Bosa, and Wisconsin has Chris Borland.
I'm just not sure what you mean. Wisconsin consistently produces high quality all-time best running backs, and they have many receivers who both perform well in college and are drafted into the NFL. Iowa produces solid TEs. Both hold their own on defense.