because she is Simone Biles. She wasn't herself that night either.
She is the GOAT, no doubt. But the US pool was not lacking in talent and I don't think finals qualification would have been in doubt without Biles. We have alternates who were ready and good enough to help bring home team gold... but they weren't given that chance.
Maybe this couldn't have been seen and the US Admin did what they thought was best. But if Biles was being pushed beyond her capabilities and if people knew she was at a breaking point then those in charge of the gymnastics program failed her and the team.