One should never make team or organizational decisions solely on what players think or want. Not only are players notoriously bad judges of talent/roster fit etc., but they may not have the same motivations as the HC or GM. Jo Jo may be the leader of the team which is fine, but he does not run the team or organization.
Noel will be no more expensive than Okafor (probably less so); the difference is when you have to extend them. But that also makes Okafor more valuable as a trade chip along with his well developed offensive game. His defense and rebounding range from awful to mediocre for a player of his size/talent.
Once Embiid leaves the game, the other team scores at will on the 76ers and usually targets Okafor. It negates whatever value Okafor brings on the offensive end. Defense is very important in the NBA and the up tempo style the 76ers want to run is launched from the defensive end. If they cannot stop anyone, it kills the effectiveness of that style. If they protect the rim, create turnovers, block shots and rebound better, that generates offensive chances for easy buckets. Easy buckets are critical in the NBA game.
Noel has his own issues, I agree his offensive game is nil, he is injury prone, his handling of this transition has been less than mature, but overall his game and skill set fit what we want to do, how we want to do it and how teams win in the NBA better than Okafor.
If I am BC, I keep my mouth shut and let things play out. There will be a team later this season that circles back or decides to finally contact the 76ers about Okafor or Noel. Hopefully, Noel will be back healthy and playing well at that point along with Okafor. That will give BC the best leverage possible to make the best deal. If he panics and deals Noel too soon or b/c "we have to get move one of them", he should get all the scorn he deserves. Patience is a virtue.