I would think they would sit him before it got to that point.
Cubs did that years ago with Jose Hernandez. It was pathetic.
I wouldn't call Moncada a bust, per se. Overhyped would be a far better term. The guy is also still 23 so he still has time to live up to the hype.
Being in the AL Central, I've followed his career somewhat closely in comparison to Jeimer Candelario. Nowhere near as hyped as Moncada but they have put in fairly similar seasons for BA, OBP and SLG.
Difference being Candelario is one year older, strikes out less and is far better defensively. Moncada, however, still has the higher ceiling as of now.