Nash appears to be happy in Phoenix. Apparently winning a championship in the twilight of his career is not the most important thing for him.
Wrong. The only reason Nash is in Phoenix is himself. He's on record as saying that he signed a contract and will fulfill his promise of the contract unless the team decides his time is up before the contract expires. Nash is too polite to demand a trade to go to a winning team. Much the opposite of the Carson Palmer situation.