That's been blown way out of proportion. Every clip in that
article other than the first one shows one of the other receivers doing the same thing - even (gasp!) Kade Warner. It's a bad look on the first one, but he's trying to not get a block in the back call. Should've been more aware and tried to pick off the next guy, but it was a bad block more than a lack of effort. Next one he and Warner are stalk blocking, neither get to their guy and are both jogging. The bubble screen is as much on Warner for getting blown up. Final clip neither he nor Williams really get their blocks, and again you don't want to get them in the back.
His perimeter blocking could absolutely improve, but this is grabbing a few clips and insisting on a specific narrative. If we're picking 4 plays from Iowa to decide whether guys are giving enough effort, I bet we can find 4 like that for any given player. I'm not saying he doesn't need to work on anything but I've never heard anyone actually close to the program question his effort.