Obviously, Steffi's numbers got inflated big time as a result of the attack, so that more or less puts her aside in the GOAT discussions, just like it does Monica. It's sad it turned out that way, but what can one do. It was a tragedy that affected both tremendously. Seles literally, but Steffi too as it made her achievements post 1993 questionable.
GOAT is really between Margaret Court and Martina Navratilova. Court edging the divine MN by a couple of inches. And there's Chris Evert and Helen Wills Moody ofcourse. Graf, Seles, and BJK are a tier lower.
I have to disagree with you a bit on this one. Obviously the attack inflated Graf's slam numbers, but to what extent we'll never know. That hardly disqualifies her from GOAT consideration though, based on a few observations:
1. She had already won the Grand Slam. If you win THE Grand Slam, you are
in the conversation.
2. Yes Seles was dominant (very dominant) from 1991-93, and...? Very
dominant doesn't equal total dominance forever, as Graf's 1987-1990
demonstrates. And Steffi was still winning a slam a year during this
period, even in what her fans would call a 'slump'. That (and their head
to head) means Graf could
turned the tables on Seles without the
3. Returning to the "inflated slam numbers" argument, let's not forget that
Court and Navratilova have weaknesses of thier own in that department.
Court has half her slams at a major not equal to the others in her era,
and Martina benefitted from a raft of injury burnouts (Austin, Jaeger) AND
played well into her mid-thirties.
As we saw with Steffi in 1999, she too could still win slams in her 30s.
What if she had kept going and caught or passed Court?
into her mid thirties.
My view is that Lenglen, Wills, Court, Navratilova, and Graf all have a claim to the GOAT. Daze
and others would add Evert (based on consistency) to the list. Maureen Connolly will forever be the biggest "what if", with Seles behind her.
Anyway that's my take. To each his or her own view. I look forward to others views.