It’s a sad commentary that we need laws to spell this out.
But, I have seen one too many people with these baggy pants. It’s both guys and girls who wear these pants, not restricted to certain ethnic groups either.
And then they are in front of you, they bend over, and you get to see the great divide. Not a pretty sight. But, they want to expose themselves. It’s good to clarify exactly what is indecent in public, since people can’t police themselves in this area.
A simpler solution is simply including exposure of one’s undergarments in the “indecent exposure” ordinance.