While this may appear to be a great, great feat, and the superlatives that were given ad infinitum, the plain fact is that this match highlighted the sheer inability of either player to create any sort of a return game. 30 percent of all points were scored on aces, while most top-level professionals rarely win when allowing more than 10-15% of points to aces.
With the invention of rackets that are designed with sweet spots all the way to the rim, which are already oversized from the 70's, along with materials that increase the amount of speed they impact on a ball, the ability to return serves is vital. Hard serves are now routine across the skill level of all ranked players. The fact that no games were broken until the 138th game of the 5th set highlights this discrepancy.
This one fact has been the main reason that I've not been a fan of professional tennis since Boris Becker. Even the great Sampras-Agasi matches did not compare to some of the great serve and volley matches of the 70's and 80's. Again, not downplaying the athletic level shown by these two tennis players, but had one of them had a decent return game, it would have been over long before they played so many games.