Whether he was being genuine or feigning this, he played this part tremendously well today.
What emperor doesn't want his might to be so overwhelming that the common people are compelled to speak the truth and not dare lie in front of him? Just like Shen Cong who, after standing in the court, has completely evolved his petty heart and could make significant decisions for the interests of the country and the people, this was the pinnacle of flattery.
It shows how good your rule, Emperor Yue, and your administration is!
Additionally, this was also a situation of retreating to advance.
Since the iron mine was exposed, it was clear that it couldn't be retained, at least not all of it! It is better to take the initiative rather than to wait for the imperial court to demand. Doing so, first, earns favor, and second, could gain more benefits.
Could Emperor Yue simply confiscate it?
Of course not, at least he has to reward something substantial! Shen Cong wouldn't lose a lot.