I wouldn't really agree that everyone is "poly". I mean that title works for what it's made for, but not for such a wide sweeping generalization as "everyone".
We are all subject to different perspectives as we are all individuals. So assuming that the social roles were reversed, and multiple loving relationships were all over the t.v, movies, next door, wherever, there would still be alot of people who would just choose one person as a lover :/
But, i kinda get your point. Deep down...you kinda want everyone to be poly
It's not so bad to dream...