That is, what they say. If you ask midjourney for the image of a Mexican man it produces this cliche. Most Mexicans don't look like that. Most will be closed to the Mexican in a suit.

I think, the result would be more diverse if you look for stick photos of Mexicab men.

This example only shows, what you can expect from every other prompt: a bias for cliches.

And yes, you are right: that is, what you ask for in Midjourney.

But you should know, that it's always a cliche.