The Sixers couldn't trade 3 in a weak draft for Noel this year, there's absolutely no way they're getting it in this next draft.
Nets pick isn't guaranteed to be top 3. At the very least, Danny Ainge also couldve really liked Jaylen Brown compared to other prospects. The Sixers could add in players like Covington and Grant, and the cavs could also throw in other offers.
I don't think it would happen, Ainge isnt the type of guy who trades draft picks away, but an owner who wants to win now may force his hands. There have been far stupider trades in basketball