The rankings are stupid, they're always stupid, they're almost intentionally stupid for the purposes of generating the attention+discussion content providers feed on. This is not news.
That said, what this indicates isn't that Smart IS the #63 player in the league, but that the voter panel collectively CONSIDERS him #63. Right or wrong, by a little or a lot, that shows that Marcus is highly respected among people who follow the league. Look at it from that perspective and it's a great compliment to one of the hardest working, toughest guys to wear green in recent years.