When looking at the depth chart, he was maybe the 8th best WR on the roster - and almost everyone ahead of him was also a 4-star or 5-star
Johnson, Watts, Austin, Lenzy, Keys, Wilkins, and Davis were all ahead of him and Styles and Colzie likely would have passed him as well.
He got his ND degree and is moving on. This kind of roster churn is normal for a healthy program competing for the playoffs. The only transfer that raised any eye brows with me was Oghoufo and that was only because he went to Texas. All the other transfers have gone to much smaller programs.