There's no danger, it doesn't warrant using his trump card against some schmuck in an academy. Is MC blind and deaf? He's not able to deduce that he's weaker than the examiner even after he watched him for a while. And also what the guy said was true, his parent who trained him, is a terrible guy. And the family who came after him are coddly bastards too.
Not going to mention the "m-muh family!" As it is a low hanging fruit