Mhhh. I'd say most women would like to be free (to do what they want), but they aren’t keen to give their partner the same degree of freedom. So, not really into open relationships, but more like "I'm so bored of monogamy".

The same goes for most men, I think. They dream about fucking around, but if their woman would do the same, they would freak out.

TL;DR: Most people dislike monogamy, but they cling to the safety that comes with it.