You're right that their faces look similar, but are their talents similar? Snow as a Sonic rookie always slowed the game on purpose while he posed a thoughtful countenance. Fans thought he must be thinking intelligent thoughts. Then he made a good pass. We knew he was good, but a guard overflow forced his trade. At the time, all including him were worried that the trade might end his career.
He wasn't known for his defense. He was the picture of a thoughtful playmaker, staying outside most of the time in McMillan style. Last week Armon Johnson looked different. He never changed the pace. He doesn't look like a pace changer like Snow. But Johnson did have very long Tarzan arms driving to the basket and in ball control. His arms have lenght and muscle, and Snow had nothing special there. Johnson under the hoop can not only muscle his way where Snow didn't, but also loop the ball with his arms.
Snow survived with his brain, while Johnson has the physical side over him. (We shall see about the thinking and the pace changing.)