My guess is they placated to him or the players on the big league team who wanted him back with them.
Either way, it wasn't beneficial to him. He did have that 1 good start vs Boston, so maybe that's not entirely true, that good start could have helped his confidence moving forward.
That said, he needs extensive work on his body, his cardio, his spin rate and velo. His velo and spin has dipped every season since his debut, and he's young, so that shouldn't happen, unless his offseason work is causing issues.