I do agree had Martina not existed Chris would be the undisputed GOAT today. Not only did Martina deny her so many slams, but Martina's total and embarassingly one sided ownage of Evert for a few years at Martina's peak is the very reason nearly everyone ranks Evert below Graf, Martina, Serena, and even Court today. Basically Chris a wonderful champion is incredibly unlucky that Martina came along, more unlucky than anyone person with any one player.
Martina on the other hand is super lucky Chris existed and played so long. Chris hardly denied Martina any slams, probably only about 3 at most, and had Chris not existed the already super weak Martina era of 82-86 would have bar none the worst competition in history, Pam Shriver would have reached #2 much of that time, and people would mostly dismiss her dominance and success due to a non existent field until teenaged Graf finally came along and easily brushed Martina in her prime aside. However as it is now people say "and she faced Chris too" and gloss over the otherwise gloomy and pathetic beyond words top 10 and womens field of the Martina era, so Martina should be grateful beyond words Chris stayed in the game so long, as she is the one who helped elevated Martina's career and legacy in peoples eyes, while doing virtually no damage to it as she was prime Martina's pigeon.
I to feel Chrissie was indisputably, one of the all time best tennis players ever. However, I also agree, that Chrissie getting her ass kicked, up and down the world by Nav's (once she got in shape, her mind and body together), made everyone forget Chrissie's dominant numbers, while only remembering Martina's dominant play and seemingly more dominant play over Evert.
The irony is, despite all those latter losses to Martina, Chrissie's all time numbers compare very favorably to Nav's anyway. That's how great Chrissie was.
Despite them taking turns in their periods of dominance,it was also due to the fact that both were specialist, and excelled in different areas (Chrissie slow, high bouncing, and Martina fast, low bouncing courts).
The major difference between Steff and Seles (compared to those two), was that Graf was an all court player and Seles was more a specialist. So ultimately, even if Seles would have won more Australians and French Opens (providing they both played a long time), Graf would have won her fair share as well. While on the other hand, Graf would have won a bunch of Wimby's, US Opens and YEC's, while Seles would have only scrapped up a few (especially with Wimby's), cause she was a much worse fast court player and could have lost to a bevy of other players not named Graf. That's the major difference.