I know there's the long COVID schtick, but I just saw my doctor on Wednesday for lingering symptoms (although I caught it twice, in July '21 and Jan '23). The first time absolutely fucked up my muscles in ways comparable to when I've experienced seizures. Sometimes that muscle pain lasts a few hours, sometimes a few days, sometimes months.
The only reason I bring that up is because post-Herm, the White Sox have such a stupid fucking philosophy with how guys have handled their injuries. It's not unreasonable to think that Moncada has just never properly healed and the med staff keeps telling him the equivalent of a high school coach's "rub some dirt on it."
And then yeah, there's the possibility that he's just fragile. That's how I feel about Eloy. But Eloy just seems to full on break and can't even swing a bat, whereas Moncada is at least playing.