One player can't magically fix the entire team, but if Wemby is your PNR defense partner, it's way easier to recover back to your man.
And it's not like elite defenders don't go over screens.
You're making it sound like Castle wouldn't be a massive defensive upgrade over Tre or Sheppard.
Imo, he'd be starting at SF early on. We had Champ starting there in most games, he's a definitive upgrade.
Obviously, it would be one of him or Jeremy on the floor, can't have both.
He can't shoot right now, I didn't say he'd average 18ppg in his rookie year. Or even during his rookie contract.
But he could get there. Many players have.
To me he's not a worse shooter or playmaker than rookie Dejounte was.
And it's obviously not a guarantee. It's a really difficult draft to get the right picks, but Castle seems like the safest bet that still has enough upside.