I think that's a little unfair on him really.
When he first joined, he actually had a pretty solid run of games. Then he got injured. Came back, was starting to slowly build some form again, and then that totally uncalled for incident with Arnautovic ruined his time here. Bellerin slotted in as the defacto number 1 right back and Debuchy never got a look in again after that. He just never got much of a proper go at it here.
He probably should've been more professional regards to his future and not mentioning other clubs who were after him. Came across as a little petulant from the whole Man Utd linkage.