It's not always who profits - often it's who will it cost to fix it and generally what will the effects of fixing it be. Inertia is powerful, so perceived cost will result in people who are actively harmed by a broken system deciding they don't want it fixed.
If it profits them, it isn't entirely broken now, is it? ;)
It's a matter of perception. We profit from the cattle industry. Most of the world doesn't - the climate, the cows themselves, ecology. But we wouldn't 'fix' it, nor would the cows.
The cattle industry could be done so much better. But as it is, it works. Nobody will change it as long as it accomplishes everyone's goals.
I'd add: If you want to know why a system remains broken, look to who profits by its brokenness.