Want to know who really makes the most money in the NFL?
It's the owners.
Owners don't have a salary cap. Owners don't blow out their knees and or shoulders. Owners don't suffer brain damage from multiple concussions. Owners don't get pushed out when they're physically used up.
Owners do get huge money — every year, guaranteed — from TV contracts, endorsements, merchandise sales, ticket sales, licensing. Many owners get the benefit of hundreds of millions of dollars in public subsidies (tax dollars) for the stadiums that their teams to play in.
The NFL has an anti-trust exemption. They use it.
If you are one of the chosen few who owns an NFL team, you cannot lose money on your investment. It's almost impossible to do so. There is virtually no risk; and franchise valuations just keep climbing.
NFL owners have a license to print money, basically.