Missing in the middle

Gotta love an article with this headline: "Milk Carton: Where has the Center Position Gone?"

It begins:

If you ever catch classic NBA games on NBA TV, even as recent as the 90′s, the game of basketball is much different. For me, the first thing that jumps out at you is the physical nature of the game. You watch Knicks games from the 90′s and a lot of those guys would have no place in today’s NBA.

The next thing you notice is the presence of a big man on every team. Even if they weren’t dominant big men, almost every team had a serviceable 7-footer. Today, most teams don’t even have a 7 footer on the roster, and if they do, they are either projects or European wing players.

What happened? Does the world have less 7 footers than 20 years ago? Unlikely. So why are there more 7-footers working in cubicles as opposed to the paint? Here are a few theories...