Yeah, it was kind of interesting at the time given Riggs had blasted Margaret Court off the court in the prior match.
I wonder if the match with King was fixed, never know for sure I guess. Still, I think Riggs was almost 25 years or more her senior which does not quite spell an even match as she was at her prime and Riggs was at best in his twilight.
Having played the game for over 50 years, I remember the match well. Watched it live on TV that day. Billie Jean kicked Rigg's ass to a frazzle...BUT given Rigg's past actions, performances, associations, and life-style, nobody who knows the game would doubt Riggs "tanked".