You misunderstand the "No True Scotsman" fallacy to apply it to this situation. There's a metric for success (graduating), and no one claimed that the only possible way that someone didn't make it is "work harder". I said that perhaps that's the reason since by the time people make it to medical school, they're on a fairly even playing field.
NTS is typically applicable when someone expresses a goal like "being a good Christian" and then continues to redefine what that means, never admitting that some are good Christians because of endless redefinitions of the metrics.
NTS is typically applicable when someone expresses a goal like "being a good Christian" and then continues to redefine what that means, never admitting that some are good Christians because of endless redefinitions of the metrics.