I think she has a respectable argument for greatest female athlete. Of course those arguments are fairly pointless. I mean, in your list you included a legendary character from a couple thousand years ago with little facts actually known…
She is lucky that female tennis is actually fairly popular compared to other sports where often the mens side will dominate.
I would put up Babe Didrikson Zaharias as one of the greatest female athletes, and certainly over Serena. She excelled in multiple sports, to include winning track and field gold medals in the Olympics and 10 LPGA tournaments.
Also surprised nobody has mentioned Paula Newby-Fraser or Chrissie Wellington in this thread.