The impression I get is that business management is primarily about people. Your employees, your customers, and how you're going to keep both happy and productive or paying. If you're in a big company, you can afford to leave the number-crunching to the accountants and the technical details to the project leaders. Leaving the managers free to deal with potential partners, irate customers, and dissatisfied employees.
So in that environment, the people who are most suited to working with people are going to be the ones that rise to the top and become the managers.
And naturally, in that environment, the people that the managers will find the hardest to connect with will be the IT people. They'll be the ones more likely to go home and watch Battlestar Galactica on a friday night than to go out to a party with co-workers. So when a manager has to choose between an IT guy, who is well-liked by everybody but not really friends with anybody, or some goof-off salesman, who does have friends who might cause trouble if he got laid off, and the manager himself doesn't like the IT guy as much as the other guy...and the other guy, being social, is somebody that the manager sees more of himself in and so believes that the other guy might even be able to get the manager's job someday...
...well, it doesn't look too good for the IT guy. So even though he might be harder-working and in general a better asset to the company than the other guy, he might get laid off purely due to people's perception of him.
But that is totally conjecture, I really have no firsthand experience with corporate IT.

So I'm curious as well.