Mahomes was quicker out of the gate than Tom because he's the better athlete. It's as simple as that. He had/has athletic traits that Tom never did. I would have thought that was obvious? Brady had to work harder than any other QB because he was never the most naturally gifted.
Now, can Mahomes last and get to where Brady was in his 40s? I would say a definitive no. I don't think Mahomes will get to 7 SBs, But he is only 28, and who can tell what will happen in the future? As a very biased Patriot fan, I hope Mahomes doesn't match Brady. But Mahomes is exceptional, and I think it is very unlikely that he won't win at least 2 more Lombardis.
it is very unusual that you have the GOAT QB who has literally hung up his cleats last year and already we have a QB who is hot on his heels. it would have been like LeBron starting off and being brilliant as Jordan was at his peak, or Tiger starting blasting off when Niklaus was at his peak,