@edsuom@inquisitormundi@mythology@antiquidons@histodons
For one, ancient Greek art usally depicts the penis to show you that a figure is male. This is especially important for gender-fluid gods like Dionysos. But you also find it in theatre: a male character has a leather phallus.
There are depictions of fully naked women, most promintently the goddess Aphrodite but mortal women as well.
Overall, there were more places where it was acceptable for men to be naked, like the palaistra.