This is a great point, and one I haven't seen anyone else bring up. I'm a little irked this hasn't crossed my mind either. But it's true that the NFLPA is going to pressure players to get all they can because its entire existence is based on improving things for the player. Accordingly, the NFLPA would frown heavily on players making deals contrary to that agenda. Obviously when a player reaches Tom Brady status he isn't concerned about backlash from the NFLPA, but a young player getting his first big contract is a different situation.
Brady got a lot of pressure each time he took team/cap friendly deals. The union position on every contract negotiation is max dollars all the time every time. Keep driving up both the top and the bottom every chance they get.
the individual player is irrelevant. It’s the players (plural).
remember, thre union is a business on its own. It’s not a charitable organization advocating for athletes. They get paid huge money by the players and those payments go to all of the lawyers, administrations and executives who work for the union.
the unions first and foremost job is to increase union revenue to pay themselves
Second is to identify and support issues important to their customers (the players), particularly the influential and powerful ones.
Third - build in plans for retired players, whether it’s healthcare, pensions, etc. these aren’t so important, as you saw when the union sold out some retiree medical benefits in exchange for near term revenues in the new CBA. Former players don’t pay dues so the union isn’t really interested in them except as it pertains to PR (owners aren’t any different on this front)