One thing to consider - Nunez is taking a prep year, so he might already be more physically mature. A benefit to a RS is not just preserving the eligibility, but also that the player gets to spend the year in the gym, lifting weights, etc., even on game days. Below is an interesting article about Villanova, who apparently has six redshirts on their roster – some for medical or eligibility reasons, but some not.
As for Nunez, his shot looks like a thing of beauty and he seems like he’ll be physically more prepared than some freshman, so there may be a spot where he could contribute, perhaps also depending on Brooks and/or Matthews’s ability to slide down or Ibi, etc.
I would caution, however, that just because it didn’t work out (for UM) with Bielfeldt or Donnal w/r/t 5th years doesn’t mean it never does. In addition to the Nova players in the article, Happ and Showalter at Wiscy both redshirted and either contributed or will contribute pretty significantly to their team as RS seniors.