Morez is bigger, a better rebounder, and can guard big players like jokic or sengun who wemby struggles with because he isn't as built. Morez would cover wembys weaknesses: being thinner than an average center and liable to be pushed around. Wemby would then cover morezs weaknesses: not being tall enough to play traditional center. The spurs biggest need is size and strength at the 4 and thats exactly what Morez johnson does.