Thanks for the research. I think those are really good numbers for the owners. They own a football team, and still making some (good) profit.
Sports is a special industry, with special interests. It is much closer to entertainment than construction. You can do a movie with an unknown leading actor and pay him pennies, or you can do it with a top seller cast and pay him tons of money, getting most of the revenue (sometimes all of it). Big studios choices second option most of the times, why? Because it is less risky.
If you want to have superstars players, that will make super audiences ratings, you have to share most of the revenues. Without these players, teams worths close to zero.