Yes and no. What it means is that a player is strong. Kevin Durant is a great player, but he's 6'11" and despite being taller than every defender he plays against, he does very little on the low block. Why? He can't back anybody down because he lacks strength. Yes, he's great, but if he were stronger, he'd be even better.
Very few players back down players now a days because of the rule changes. Bench pressing is way down the list with me when it comes to evaluating basketball players.