I would definitely agree with that claim, then. It seemed to me like he was making a far stronger claim, but it's very possible I'm wrong.
The "norm" (average) for money managers can be achieved by having half the money managers lose money to the other half. This works well for them, because when they win they win, and when they lose someone else pays. Money managers can go big or go home, and keep trying, because in the long run they're not eating the losses.
But people betting their own money on the same strategies actually lose their own money when they lose.