So far, every other Olympian, or other serious athlete, interviewed has said Simone Biles did...

[Another Jackalope]

22. They apparently come on suddenly

https://www.nbcsports.com/northwest/tokyo-olympics/twisties-biles-exit-brings-attention-athletes-mental-health

The “twisties” in gymnastics refer to a phenomenon wherein an experienced athlete suddenly loses their sense of where their body is in space – a sense that is crucial to the sport and the sudden loss of which could result not just in an Olympic loss but in serious bodily injury or even paralysis.

Gymnast Laurie Hernandez, Biles’ 2016 Olympic teammate, told Olympics.com that the so-called twisties can set in just as a gymnast attempts a high-level skill, when even a slight misstep could carry grave consequences.

“The rhythm is off, and your brain will like, stutter step for half a second, and that’s enough to throw off the whole skill,” Hernandez told Olympics.com. “And, so, it happens, and it takes a second to get over that.”

“What I think is really important here is, you have Simone, who clearly knew something wasn’t quite right, and when you are flying and flipping and turning 10, 15 feet above the floor, looking for a landing, you better be in the right headspace or really bad things are going to happen.”