Having seen both of them play in college and Okafor play in high school, I disagree with this. Okafor is a once in a generation big in terms of low-post refinement coming into the league. I think that Russell will become the best passer in the league as Lebron and Paul start to decline but I'm not convinced he will have more of an impact over time as someone like Wall or Irving (even though Russell is already a better playmaker than the latter). Russell will need a great big or wing player to be the primary scorer on offense and will need to improve defensively (didn't like what I saw when he went up against McConnell). Okafor will be a top 3-5 big man for a decent chunk of his career and will be the primary offensive option on a contending team. I think the reason that Okafor has fallen in terms of hype is because of the potential of Towns as a stretch big, a defender, and a big that can run the floor; the NBA is trending towards these sorts of players as they add significant potency to an offense (this is why I would draft Towns over Okafor). With that said, I personally think that it's easier to develop a shooting touch than it is to develop consistent post moves and Okafor already seems like he will trend in a similar fashion to a legendary big, Tim Duncan.
Both Russell and Okafor will be all stars though and the Lakers need a PG more than a big man, especially if they plan on keeping Randle. Ultimately, it's far more important how a team builds around each of them rather than who is better/has more potential right now. If you put Okafor with another low-post big, that will lead to problems. If you give Russell no wing or post scorers that will lead to problems. Towns is probably the only player that can fit into most, if not all, NBA systems.