Two different situations here.

Brady "got his" already, this is gravy for him.
Like it or not (spygate) he is runnig for the title of best ever QB. His legacy is all that he needs to play for.
The whole "spygate" thing makes it even more important to do it without that cloud.

This is Flaccos ONE CHANCE to get his elite QB payday. He aint an all time great QB.
He will NEVER again command elite QB money, it is his one chance at the big payday.

Any reasonable deal will STILL result in the loss of key players, along with age. lowering his demands wont get them more rings.

He never gets the respect that he think he deserves and he will demand respect be given in terms of this contract.

Flacco is gonna get paid, and he aint gonna play nice.

Brady is about his legacy now, two players in very different situations.