I don't think that the point of the myth lies to the fact that it was Pandora that openned the box, neither that the box necessarily symbolizes the womb. It could have been her husband, Epimetheus, that oppened it, and it wouldn't matter, the result would be the same. What matters is that Zeus knew all along that the box would be openned. The box was given to the couple as their wedding gift by Zeus, and he wanted to punish humanity this way, because humanity accepted the gift of the Holy Flame stolen by Prometheus. That made the humans more powerful than they were, and some of them became greedy and invaded Olympus to overthrow the gods, and become rulers in their place. Zeus zapped those who even tried to climb Olympus with lighnings, and to take revenge he thought of that trick with the box.
So basically the main point of the story is that accepting stolen goods is bad.
Note that Pandora's husband, Epimetheus is NOT a man. He is a Titan. Humanity prior to Pandora existed as beings that had no sexes and were given birth by Earth, literaly (According to the myth) sprouting out of soil like plants do. Thus women through Pandora is the oldest sex of the two. This is not something explicitly written, but one is lead to that conclusion one he realizes that the first humans didn't had a gender / sex and had no sex.