Assuming the truth of some rumors (and possibly not others) - Belichick deserves criticism for how he chose to make this decision - not giving adequate reasoning given the controversial nature of the plan, leaving players in the dark, causing division and blame in the locker room, etc.
But otherwise, you're completely right. We know there were reasons for what happened, and we know the outcome, and we (meaning Patsfans generally) are just filling in the gaps with guesses based on old or meaningless information.