Is the phrase "My brother, you are the most foolish of God's creation, by God" considered a Ghamus oath or merely a form of hyperbole?

Describing a person as foolish, especially swearing that they are "the most foolish of Allah's creation," is an obscenity in speech and contrary to the good words that a believer should utter, as the Messenger of Allah, peace and blessings be upon him, said: «The believer is not a slanderer, nor a curser, nor an obscene person, nor an indecent person.» The one who says such a thing must repent to Allah.

The intention of the one who says this is often not to survey the most foolish of Allah's creation, but rather to exaggerate in describing the interlocutor as foolish. This can be understood in two ways: First, by تقدير "من" (implying "of"), meaning "one of the most foolish of Allah's creation," similar to "the best of you is the best to his family." Second, by using the صيغة التفضيل (superlative form) for exaggeration of the quality, not for comparison, such as "Allah is more merciful to His servants."

If the described person is indeed foolish based on their words or actions, then the one who swore does not break their oath, even if they used the superlative form.