The situation is a lot messier than that blurb -
Long story short, "the NFL" is (legally) 32 distinct businesses that can (legally) collude in some ways, as in they can set universal salary caps, floors, etc., _only_ because they have an agreement between the teams and the NFLPA.
Similarly, the only reason the networks make TV deals with "the NFL", vs deals with each individual team, is legally because of the national Sports Broadcasting Act of 1961, which allows the NFL the right to do so, apparently under the logic that while not having the businesses (the teams) make individual deals with networks is anti-competitive, the consumer wins out because all the games are effectively free to watch on the TV...
... until there's a ton of deals for internet rights that are not free for everyone, killing the justification for that 1961 Act.
This gets very murky, and ties into the same legal issues with things like NFL Sunday Ticket, if the NFL is actually 32 independent businesses.
Try giving this a watch if you're interested