Bronze and king are both positions in the game "the glory of the king", bronze is the lowest position and the game is the most delicious; The king is the highest position in the game and the most powerful role in the game. So these two words are put together, and the contrast is strong.
Nowadays, the bronze king is often used to describe a person on the Internet. We often see that some videos seem to be very powerful at first. Everyone thinks he is the king, but in the end he is still weak or timid. At this time, everyone will describe him as bronze.
If it feels impossible at first, it will surprise people at last, which makes people feel very powerful. At this time, people often use what they thought was bronze but didn't expect to be a king to describe such a situation.