I’m betting that he had a falling out with the offensive staff.
He probably went to them complaining about his perceived lack of targets or underwhelming stats, and they probably told him some hard truths. I’m also betting that film study wasn’t especially fun for him this week when he is shown getting pushed around by Oregon’s D.
I’m also suspecting that he’s had family and friends in his ear telling him how wonderful he is, and how much greener the grass will be somewhere else.
Bottom line, he quit on the team, and he put his own stats and glory above the team. I honestly don’t care where a player with that attitude ends up.