Stefi Graff retired when she was 30 with 22 grand slam titles. Serena has 23 titles.
Also Steffi is the only player in history to win the Golden Slam— all four GS titles in one year and Olympic gold too.
All in 1988.
I’m not a fan of Serena at all. Her arrogance and poor attitude ruined women’s tennis for me for awhile.
Interesting conversation on the Tennis Podcast about how Graff’s ascent followed Monica Seles’ stabbing:
https://play.acast.com/s/thetennispodcast/slidingdoors-part1