Why do women wear different underwear than men?

men have to deal with a penis and balls flopping around, and briefs support the balls, whereas boxers just add an extra layer so that the flopping is not obvious

and with females they don't have anything moving outside of their body in that region

generic female panties are a lot like briefs, but briefs are more pronounced as to support the penis and balls, but allow enough room for them to be comfortable