The Sixers have a solid GM* and a solid coach already in place (much like the Celtics). What they're lacking, obviously, is a good basketball team. You don't get rid of the two sides of the triangle you already have when you've just got to focus on the last third.
*And, yes, it's a fair criticism that Hinkie hasn't constructed an actual NBA roster, so how can he be considered a good GM, but I don't think he's actually "lost" a trade (that I've seen) in terms of value exchanged. It's not like he's Billy King or something.
Also what's the deal with Ben Simmons. Is he going to be 'the guy' of the 2016 draft?