I remain unconvinced that this shift is taking place on the scale you're referencing. Search is a fundamental web activity that isn't mutually exclusive from "social surfacing" for discovering content. Rather, they are complimentary to each other and the main points of differentiation are with branding and marketing rather than any specific shift toward one or the other.

I also think its a bit simplistic to state 'Facebook works the way humans work' as people hear about stuff through numerous other channels than the people around them (ie: nyt.com dining & wine section for a new restaurant).

The 'crazy AI gymnastics' Google is doing isn't for nothing. I actually think those gymnastics are advancing the web in ways other companies aren't. There will always be some overhead to interacting with your friends on the web and those gymnastics Google is doing make the web a better platform for people to interact with (more like your friend).