US English language users now can search for all 2 trillion posts on Facebook. The new search engine includes all public posts. So you can search without any limits and find all related posts, even if a person is not your friend. Of course, your search results will be personalized. About 200 factors are used, to give you the most relevant result.
From the one hand, it should increase content engagement because now your posts could be viewed by non-friends. And it will provoke you to post more. From the other, it is a well-understood channel of monetization. Though Facebook search team is not focused on cash right now, they confirm that "it will come when it makes sense".