What about that stretch where Sabatini won 7 out of 8 vs Graf. Did you feel Graf was a given to pull it out vs Sabatini in the big situations then?
It is true players that are exceptional at a young age tend to be overrated. Capriati is an example of this. People even today talk about her like she was an all time great talent who should have taken over from Graf and Seles and dominated for years. Some people just naturally reach their apex in talent at a younger age, it doesn't mean they are necessarily more talented. Although in the case of Sanchez vs Sabatini I do think Sabatini was overall more talented. However Sanchez's talents were so extreme in one particular area- she might be the best defensive player in history, that in many ways it probably meant more than Sabatini's more versatile and complete game all put together, even before considering their work ethics and respective mentalities. I do think people underrate her in some sense in that she was the hardest player to put balls past I have ever seen, and that is incredibly hard to oppose, and she did have some offensive capability too (backhand, volleys, even developed a somewhat strong first serve in the mid 90s for awhile).
I think the point of the OP though is that it is more than about your winnings and how great a player you are, but also the intangible factors that make you stylish, loved, remembered. And in that respect I can see how the talented enigmatic Sabatini, who was a great player who would win more than 1 slam in almost any other era (Sanchez would probably even win more than 4 if she were peaking in the era Wozniacki was #1 too BTW); and who is beautiful, stylish, played an interesting and eye pleasing game, and has a huge fan base, would fit that bill.
I agree that Gabriela underachieved and in a different era could have been more successful. Ultimately, though, her mentality held her back at some point.
Again, I admit to having a large bias towards Sanchez-Vicario, but I just find it hard to agree to the fact that Gabriela was the better player or the more "talented" player. It is hard to argue against a player who won 4 slams vs a player who won 1, but when you add in the fact that Arantxa was RUP in 8 other slams, while Gabby was runner-up in only 2 other slams, I just don't see how that argument fits.
You said it yourself that Sabatini only had 1 slam win vs Graf. Simply put, when the pressure was on, you knew who could perform and who couldn't.
I didn't realize Gabriela won 7/8 against Graf. Very impressive...but also shows her ability to beat Graf was limited to a small time frame. Still, though, other than a tour championship victory, the one match that Sabatini lost in those 8 was their only grandslam meeting. My memory may be flawed, but I don't ever remember past 90 thinking Sabatini might beat Graf at a slam. Again, bias may very well be playing a part in this.
As for the winning H2H against Arantxa, it was 12-11 and Gabriella won the first 7. Granted Gabby was past her peak when Arantxa won the last 4, but still, I don't know how much can be read in to their H2H since they both had their own different peak times.
Either way, I miss both players. As you said Arantxa was one of the best defensive players of all times and Gabriela was stylish and clearly underachieved.
As for 2010 and 2011 when Caroline Wozniacki was number one...in 2010 Vera Zvonereva was #2 in the race. Both Sabatini and Sanchez were considerably more talented then either of those players. Schiavone was #6 and the French Open champion...both Sabatini and Sanchez would have pulverized her on the clay of Roland Garros.
2011 wasn't much different...Na Li could not out compete Arantxa and Gabriela at a French Open, and again Francesca made her way to the final of that slam.