Let’s mostly back out Nadal and Djokovic by seeing what Fed did vs players ranked outside the top-3:
2004-2007: 298-18, lost 5.696%
2008-2013: 317-41, lost 11.45%
Fed’s losing rate vs players ranked outside the top-3 doubled. It increased by 101% after the 2004-2007 period. His play vs the so-caller weaker players got much worse.
So what happened? The racket technology got bigger while the courts slowed down. Brad Gilbert made two comments about these things. In 2011, he owned a pro tennis shop. Many customers complained that Gilbert didn’t carry Fed’s 90 inch racket. Gilbert said in 2011 that “with that racket, you need to hit it flush, and I mean flush”. Another quote of Gilbert’s at the USO: “these courts have slowed down drastically. Lendl would have cleaned up at the USO with these courts”. That tells the whole story about how outdated Fed’s racket was in 2011. Brad Gilbert wouldn’t sell the racket of the most popular player on the planet because it was that outdated and junky. Note: Fed finally switched rackets in 2014 and he experienced somewhat of a Renaissance. But he was 32 going on 33. That racket allowed him to reverse some HTH matches while improving his record vs the top 10(when compared to 2008-13. He was 196-24 vs players ranked outside the top-3; a loss percentage of 10.91% vs that group. So although that is slightly better than his 2008-2013 numbers; it’s not close to his 2004-2007 numbers.
I saw Agassi get interviewed in late-2004. He was asked why Fed got so much better so quickly. Agassi said that it was all attributed to his movement. “He’s always had the shot-making. But his movement is so much better these days..”
As a fan, I can only dream what Fed would have done with the larger racket from the beginning. Agassi figured it out very early. He was using a 107 inch racket in the 1990s. And many call him the best pure ball-striker of all time.
But at the end of the day, I cannot give a player credit for a what if. Fed’s records were broken fair square. However, we need to respect what Federer did. He’s the only one from his generation that survived the seismic shift in the change of the game. Somebody should watch the 2003 Wimbledon final once to see how often Fed served and volleyed. At age 19, Fed with the same 85 inch Wilson racket that Sampras had, served and volleyed the majority of the time vs his idol. Now granted, the grass was different that year(the slicker grass was changed out in 2001). But that’s not the point. Fed learned to play a different brand of tennis on grass courts when he was younger. I really wish that Fed had switched to a 95-100 inch racket in 2002 instead of going to a 90. But that is life.