Probably true, but If he's concerned that they won't offer the super max if he doesn't look quite the same, then why would he be any more confident that they would if he barely plays?
Unless they have it on strong authority that this is a Roy, Granger, Stoudemire type situation (which is highly doubtful), they're offering him the super max either way. If he doesn't already, they won't risk alienating him to the point where he wants out.
Short of believing Brown or Tatum can become at least a top 10 player (again, highly doubtful), the alternative is banishment from even thinking of contending until they can luck into drafting that caliber of player again. Look no further than most franchises to find out rare that is.