Hard disagree, he is only just about to turn 28, most elite CBs are very good into their early 30's.....I think you are vastly underestimating how difficult it is to find a truly elite cover corner.....
You don't "easily replace" the best CB the Saints have ever had.....And during that 7 game stretch we lost against the Rams and the Lions, the only teams we played in that stretch with good QB's, I'm willing to bet he would have made a difference in those games....