It makes since and it doesn't. Afflalo is 28 and they have Oladipo so there is no real reason to keep him on a young team because by the time everyone matures his contract will be up. They also need a 4 so on paper it makes since. However, Gibson is not that young. He turns 29 in two days. So again by the time their cor young players matures he will be32 looking for a new deal and probably itching to play for a contender.
Gibson's age is probably a factor but I doubt he is involved. More than likely they trade their Euro(Mirotic), stretch 4, and one of their picks for Arron and a future pick. Orlando will have cap space next year to pay Mirotic and his is a young piece to add to their growing team at a position of need.