What are the olympic rules? At what point could an alternate have subbed in for Simone? Could she have withdrawn before Team Finals and an alternate have gone in instead of her, or would it have been too late at that point?What (possibly) triggered her today may not have during team qualifying - or maybe she was fighting through it then and realized she just couldn't today. We don't know what we don't know.
Either way, in my opinion, everyone did their best and I'm immensely happy for the team. "Disappointment" is very subjective. Not trying to sound harsh, but I would hope the alternates realized that there might have been a chance they would not actually get to compete, depending on circumstances.