This...this guy gets it! Someone give him a medal quickly! YES! This is what i'm always saying over and over anv over again non-stop...nobody wants to hear the truth, but if dug tennis history deeper there was always a reason for an ATG of the past to underperform i ntheir early 30's, which has nothing to do with their age! For Borg it was emotional burnout, for McEnroe - he could not adjust to technology, for Wilander - drugs got on the way, for Sampras - lack of motivation cuz at the time he held most records and had no reason to keep going anymore, for Agassi he wanted to retire and be a family man close with Steffi and found their tennis academy...for none of them age alone was the reason they couldn't keep dominating i ntheir 30's! There were hundreds of other factors, other than game itself being too strict physically for someone, who is in his 30's!...
Thanks for the praises, and the same goes back to you. Great post as well! I might add that in the past it generally often changed what the current "winning style" was (of course as a result of racquet changes, but also surface changes and, as you said, just many combined factors). For example McEnroe won his matches on a certain talent in net play and generally what we call "touch". Then the power serve-and-volley era came up (now contrary to before with the serve being more important than the volley), and he could be overpowered by newer racquets. And later serve and volley itself was obsolete because it's gambling to a large degree, and after a good serve a good first forehand with modern racquets is just the same putaway shot as a good first volley, while after a weaker serve when staying back you won't get passed immediately and still have the chance to construct the point otherwise.
Yes, Sampras also didn't decline due to age, and with him I don't even think it was motivation. IMO it was mainly a combination of two factors: Annacone is a bad coach who ruined his all-court game by telling him he has to come to the net EVEN MORE because he's "old", while in reality the game changed to the opposite direction in that same moment. It doubled the effect, because literally when others stepped forward, he stepped backwards. Secondly Sampras was very stubborn and refused to change racquets. In consequence, someone like Hewitt started to beat him routinely. Maybe not because he was "better" in absolute terms, but he was the better niche player for the upcoming dominating factor.
And this development as it happened showed it to be patently absurd to think Sampras could beat Djokovic nowadays with his style from the 90s, be it on old Wimbledon grass, new Wimbledon grass or elsewhere. And I say this as a childhood Sampras fan. It's just too easily to be seen out of the information we have. I don't get it why so many others don't want it to be true. I mean, Djokovic is literally Agassi and Hewitt combined (in terms of pure ballstriking/returning plus defense/movement) in an era where this is explicitly required, and yet Sampras beats him with serve and volley? Yeah, sure...
Almost all top players of the rapidly changing eras were niche players. The saying "a great champion will be a great champion in any era" is completely wrong. Very few would have been. Simply because the game was almost a different sport if we compare some eras. To think someone like McEnroe could compete at the top in a baseline basher era is absurd. If we assume he could just do everything differently right from the start, we would 1) create a completely hypothetical person with just the same name, and 2) disregard what "talent" means. You will always be more talented for either this or that, and not simply have talent for anything that was ever called "tennis". I'm sure there are many players with similar talent for a certain aspect of the game as some ATGs, but we never heared of them because they were born in an era when this aspect didn't matter. Who knows, maybe someone like Cressy even is the Becker/Edberg of this era.
If we consider that the Big 3 never had to change much and could be sure that their style and technology would be the dominating one over their whole careers AND that they are the most talented players for that style AND the general advance in fitness/health strategies AND that they have the never fading motivation to compete for history against each other, then their results are not too surprising, and others don't have to be "mugs" for that. I would even say that the Big 3 are so good and relentless in what they do that contrary to most past champions even if conditions would have slowly changed into a different direction again, they would still have continued to dominate for a while.
One last word on Agassi: He really is a good example that age wasn't that important. He is the opposite of Sampras in a sense that he started when his style wasn't the one considered to be that great for the then current conditions, but later conditions changed in his favour. So some of his later results were better and more consistent than ever. And he also showed that it is much more about motivation and mentality than age either. When he had mental issues, he was absurdly bad even in his mid 20s. When he was motivated again, he became a top player again in his 30s. It's like he always had the same CHANCES to be good up to age 35.