Just in case there are people who actually don’t know, Riggs easily beat women who were better than BJK at that time. He took a dive. Yes, the media was playing you way back then.
Yes, Riggs beat Margaret Court who was ranked No. 1 at the time. He beat her easily too.
There is no way Billie Jean King would have challenged him unless she knew she would have the game handed to her. The fact that the game was played was enough to know it was rigged.