But if Simone Biles is actually on the same side as Riley Gaines, why was she attacking her?
I actually think it is really unfortunate that Riley Gaines is a prominent Trump supporter, because it makes it far too easy to dismiss everything she says as bigotry.
Simone clearly doesn't believe that trans women should compete in women's sports. She tweeted as much in 2017, and even now she is talking about separate categories for trans people (and getting a lot of flack from trans activists). So when you come down to it, her position is basically the same as Riley's.
The difference is that she isn't brave enough to say so. She's the sporting equivalent of Margaret Atwood rather than JK Rowling.
I don't actually blame her for not wanting to tweet, "trans women should not compete in women's sporting categories" in the current political climate. Everyone with even a passing acquaintance with trans rights activists understands that saying things like that, when you are a well known public figure, and even when the majority of ordinary people agree with you, opens you up to a torrent of abuse from insane activists who will not let up until you have been comprehensively cancelled and your reputation is trashed. The situation is perhaps particularly delicate for retired athletes, who rely on their reputation and public image (and very little else) to continue to earn an income through sponsorship and media appearances. JK Rowling can continue to write novels which people will continue to buy. (And even if she never sold another book, she doesn't need to worry about money anyway.) Even Margaret Atwood doesn't need to "work" anymore because she's in her 80s. Simone Biles is 28 years old and her reputation is all she has. If she gets cancelled by trans activists and brands no longer want to be associated with her, she has nothing.
If Simone Biles had said nothing at all, I wouldn't blame her in the slightest.
But she chose to publicly call out Riley Gaines, implying (but not actually saying) that she supports the inclusion of trans women in women's sports. It was completely uncalled for virtue signalling, and it is the very epitome of punching down, both on a less successful athlete and on girls and women with sporting dreams everywhere.