Peak early? Like, after a few world and Olympic titles?
I love the enthusiasm, but it's not absurd to think he could somehow breakdown - physically or otherwise - and never win another Gold.
Too often people assume trajectory or constant success. Rory McIllroy, Aaron Judge, Grant Hill, etc. Just because they have brilliant success early you can't simply tack on the trajectory permanently.
What he's already done is amazing, nearly inconceivable, and he is on track to be the greatest ever.