Facebook has been ranking the posts in your News Feed for a long time. The incentives are aligned, Facebook wants you to engage with items in your News Feed. Page owners want people to engage with their posts. If you don't like it as a user, you can change the News Feed sort to "Most Recent." Advertisers who don't want engagement can potentially buy different kinds of ad units to accomplish whatever it is that you care about (clicks, sales, etc).
I do think Facebook wants to keep you on Facebook, so they paid attention first to making "native" ads that work on Facebook. If you are only going for traffic to your site, you are not using your Facebook Page for what it's best at, which is helping you naturally become part of a conversation that people are having with their friends. I think that's very meaningful and a much better advertising experience. If you care about traffic, Twitter's promoted tweets are very good at sending traffic to your site. If you think about it, that also makes sense because that's what's "natural" on Twitter (i.e. we use Twitter to discover interesting content online that we can then click on to go consume).
With that said, Mark Cuban did recently get really angry about this too (https://www.facebook.com/photo.php?fbid=460717227304430&...) and I understand why. He worked hard to get 2.3M fans on Facebook for the Dallas Mavericks because that's what Facebook was about before. But then a post only reached 27k fans organically and he was asked to pony up $3k to reach ~50% of his fans. That just sounds too much like blackmail. Facebook failed to communicate and manage the expectations of Page owners. They didn't know that their posts were never reaching 100% of the fans, and when that became apparent, they noticed that the algorithm was updated and depressed the reach numbers significantly. With the recent IPO, Page owners think Facebook is money hungry, and then they noticed the new Promoted Posts so they fired back. Facebook could've just communicated more to manage people's expectations along the way.