This really isn't even debatable. Fed's prime was 2003-2007. But the first signs of his decline were apparent in 2007. And his decline came completely to fruition.
The fact is that 4 of the 8 GS finals that they have played against one another happened post-prime for Federer. Nadal was under 25 for all of them (24 in the last one).
Two of them happened on clay (Nadal's best surface).
Only one of the defeats was on grass. (Fed's 2nd best surface).
None were at the US Open (Fed's best surface).
One at the Aussie.
Before 2008 they were 2-2 against each other in GS finals. You don't think the dramatic shift that happened after that year had anything to do with age? Nadal going through the meat of his prime years while Fed slowly declined?
And look I have a ton of respect for Nadal. I don't hate the guy, I enjoy watching him play, think he is a great champion and that he has been great for the sport. But it frustrates me when people post numbers and don't provide context - "Fed sucks, GOAT time my ass - he is 2-6 against Nadal in GS finals!" How can they ignore the obvious age difference?
Nadal is 5 years younger than Federer. 5 YEARS! That is a huge gap in their age. If it were 1, 2 or even 3 it wouldn't be that big of a deal but 5 years is half a damn decade!
This is why it was always silly to overly compare their careers. Nadal (26), Nole (25), and Murray (25) was always a much better comparison. They're essentially in the same generation.
Good post. For most i would assume Federer's results would convey his decline. I remember watching his Us Open series matches vs Ginepri and Karlovic thinking i was watching a completely different player. Reading over this forum before i posted the last month, i was shocked reading that Federer played guys off lesser calibur than today...what bullshit. Fed in his prime had a harder time winning some wimbys than this one where he is much older and injured.
Fact of the matter, which some djokovic/nadal fans hate to admit, is that maybe their guys arnt as good as they think they are. For instance if Novak is so great and Fed lucky to miss him in his era, how does he lose to a 31 year old fed (back injury on top) in his prime after his most successful year. He didn't just lose, he was completely outplayed. Same goes for Murray.