If Brook has a shot then Thurman and Spence both dude firstly they are strong at the weight and are much bigger than bud.
True, Thurman very fast, very strong, Spence is even bigger, stronger, but look how Thurman struggled with Cuello. They both good, but it's Bud that has signs of greatness. He'll be getting belts all the way to 154. Just watch how powerpunchers like Thurman start real fast, real strong, then by midfight, they start fading. Crawford is the opposite, he only gets stronger as the fight goes on and by then is already figuring an opponent out. Brook throws better combinations than Thurman and Spence, those 2 in love with their power too much, they start struggling when their opponent is taking their power well and is still standing. Brook is a step above.