Not necessarily. There are many players in league history who have passed by big money to retire when they are unhappy like Barry Sanders or Calvin Johnson. Several prominent 49ers players retired early during the end of Jim Harbaugh's tenure. Derek Carr supposedly wants to be a pastor, much like Tony Dungy or Reggie White. He also had two concussions this year and the year is not done. If Carr is happy he will definitely stick around to collect that check and still probably suck. If he is unhappy, anything is possible, so I would take my chances and make him unhappy.

Also, Derek Carr has a no trade clause. If he would agree to a trade, there are many possibilities to move a draft pick or player to unload some or all of his salary. For instance we could trade Adebo and Carr to some team for a 7th round pick. But Carr has to agree to the trade. Best way to get him to agree is to make him think its his idea. Best way to make it his idea is to make him unhappy.