That's exactly the point. Player development to a large degree depends on the player regardless of how good the coach or organization is.
By all accounts, Okafor has done everything the Sixers asked him to over the last year or so and is currently in fantastic shape. If he was 40 pounds overweight and the Sixers were making noise about Okafor spending the summer in clubs I'd get the point you're making, but it just doesn't seem applicable here. There are very real concerns about whether Okafor would fit at all and whether the exception would be better used elsewhere, but I really don't have any concerns about him coming in with a poor attitude and refusing to work.
Last year or so? He didn't get in shape until this offseason. That's a start but I've yet to hear him talking about his deficiencies as a player and his efforts to improve them. Is he working on his defense? His rebounding? Expanding his shooting range? He's talking about his career and playing time. If we get him and he's still riding the bench which he almost certainly will, what is his attitude going to be?
I'm not saying Okafor is a lost cause. But he's a project with an upside of Eric Kanter right now. We're not the right team for him.
It’s really unclear what happened with Okafor over the last 18 or so months.
He had a minor procedure in March 2016, that had a six week recovery time. But he wasn’t ready for training camp seven months later, and then had surgery again this past March having supposedly felt discomfort all season. Now, it’s entirely possible that Okafor blew off his rehab. If he played for any other team I’d be set to believe that’s what happened. But with all the question marks the last few years coming from Philly on injuries, from Embiid, then Simmons, and now Fultz, it seems credible that in fact the Sixers either messed up Okafor’s initial procedure or lied about the severity in order to keep up his trade value.
In short, I just don’t know what to make of what happened to Okafor. His rookie season went as expected — some dominant inside play on offense, some questionable defense, and a lot of inconsistency. And then he got hurt, and his career quickly went off the rails, but it’s unclear if that was due to injury, the Sixers inability to play him with a superior Embiid, or Okafor’s own attitude/lack of development.