I don't think it's sexism, it's simply people following their interests because they can. Women have the upper hand on dating and can afford to be picky since they don't have to compete on anything, so they use it for their own advantage. Sure, on can argue that men can manipulate them on seduction, but if that happens, they can move to the next one if they feel they need to.

Society isn't going to change any time soon on this. A very simple example is to look at the front page of reddit and see how many posts you can find about a girl proposing to a guy. This is just how society works: the guy always provides the ring, not the girl in a straight relationship, and this tradition has really strong roots that are the foundation of how all this works.