They tried with Google+, there's was nothing stopping people from using Google to socialize, no-one wants to.
isn't Google Contacts a digital Rolodex? What you're describing sounds like white pages.
Google contacts has the downside of inserting everyone’s birthday into my calendar. I can’t remove a birthday from a contact once Google knows it. Super annoying and a dumb example of trying to use shared cloud data instead of my locally curated contacts list.