Why does hamlet comment on alexander the great when he is looking at all the skulls on the ground?

The idea Shakespeare is trying to make is that everyone, no matter how great, will die.

All of the skulls on the ground are equal. It is no longer clear whether they once were man or woman, rich or poor, master or slave. In death everyone is equal, and even someone like Alexander the Great will end up the same as a poor servant.

It is the poet alfred, lord tennyson himself