It's because Manning was superhuman in the regular season, that he can stay in this convo. No every year wasn't excellent, who has a great year every season of their career? This wasn't a great year by Patrick Mahomes

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I'm more objective than most people here. The fact that Manning routinely went south in January is why he could never be the GOAT. It's why even though I think he was a better player than Montana, I can't in good faith rank him historically higher than a guy who was significantly better than Manning in the playoffs, AND doubled his ring count...
I don't even factor in Manning's last ring into my analysis of him, it's Y2 to Y17 that he was eating shyt up and he only won 1 ring in that stretch, but he was so absurdly dominant at his peak, I can't say a guy who is just 7 years into his career, belongs higher than a guy a believe had the highest peak from a quarterback in league history; held that peak play longer than everyone; and was a consistent winner...
Manning in his prime led The League in TDs 4x, led The League in yards 3x, led The League in passer rating 3x, led The League in completion percentage 2x. That's
12 times leading the NFL in a permier quarterback category. Mahomes has currently led the NFL 3x in something (twice in touchdowns, once in yards)...
It's like what are we talking about here? The fact Mahomes is deserving of a conversation with Peyton Manning says everything about how great Mahomes is so soon. But to me, when I'm comparing guys across eras, the degree of dominance matters. I detailed in a recent thread how Mahomes' run started at a very advantageous point, when old era guys were heading towards retirement, and his era peers were either as yet undrafted, or not yet into their respective primes...
I'm very clear bro, there's a gap between Mahomes and everyone else, but he's now entering a phase where there's a bunch of guys, it's about to be very similar to the era Peyton and Brady dominated. Just real quarterbacks everywhere, it really hasn't been that for Pat, and kudos to him for taking advantage of that void. But he hasn't yet just dominated a league with elite quarterback play league-wide. And unlike Manning, there isn't any skill or statistical separation from Mahomes to the closest guys...