Spence fighting Thurman at 154 is PBC's way of keeping him viable at 147. It's a built in excuse. He can't afford to lose or even look bad against Thuman at 147. His value at the negotiating table would drop and ole Haymon don't want that. He has an excuse at 154.
If Spence is having problems making 147, he's going to hate trying to make it again if he fights at 154. He's not going to fight at 147 ever again. It's Haymon's final chess move to make sure Spence vs. Crawford doesn't happen at 147.
Because he's a PBC fighter. And there's every chance Spence would beat Charlo first fight at the new weight. I don't think Spence will be around for much longer. I think he'll fight at 154 once and then maybe look for a catchweight fight after the Thurman fight to try to make big coin. He shouldn't be fighting with his eye the way it is.
Spence never wanted to fight Crawford. Bud messed up the most recent negotiation but past that it was all PBC and "across the street" bull****