Besides it being a terrible return for the Rapters, the notion that you'd do a complete tear down of the best regular season team in the East is not based in reality. Just because they play like crap against Lebron doesn't mean they would have against us.
Moving Lowry and Ibaka, if that's possible, makes sense to try to reformulate the team. Moving Derozan for anything less than a star level return doesn't. He's in his prime, playing at the top of his game and has 3 years left on a reasonable contract.