Keon looks like a player who's lost his confidence. I agreed with the Steve Smith take, particularly the rep where he's cradling an easy catch on the slant and getting nothing out of it.
It looks like Josh has lost confidence in him as well. We were forcing more balls to him early in the season and Keon wasn't coming up with them. That has to be tough on his psyche. A more mentally tough player would persevere, but it's tough to stay confident when you're not having any success and you can literally see the QB losing confidence in real time on film (despite having worked together all off season to make sure you were on the same page).
I don't see Keon recovering from this at least on Bills. We can talk all we want about moving him around, but Kincaid and Shakir are better slot options. We should look to trade him in the off season assuming he has any value at all. If not, he's WR4 next year.