As for Facebook, I think anyone who ever had a positive opinion of them should be evaluated by a psychiatrist.
The terms "Googley" and "Googler" quickly became the equivalent of nails on a chalkboard to me thanks to these people.
You clearly don't understand what a manager does if you believe what they do isn't work.
But then again, managers are very skilled at power games, and the ultimate sign of power is taking credit for what your subordinates produced.
IMO both of them are already on a plateau. Google keeps abandoning products, Facebook keeps buying promising startups and quietly shuts them down (Google does it too). In Google this mostly happens due to some weird geekdom culture / peer pressure thing (coding hipster-ism?), and in Facebook it's more like "we want to conquer the world".
Both companies' strategies are not sustainable. The world is already catching up and I suspect that now it's time for suing the hell out of everybody who isn't sharing their vision while being even slightly competitive to them (opinion, not a fact, no evidence for that, don't kill me).
One only needs to follow recent HN for news about decentralization efforts and slightly increased amount of articles about self-hosting to understand that a good part of the tech world is getting fed up with Google and Facebook.
I would. Where do I sign up?
I predict that the Golden years of FB and Google are right now, they will slowly head into a plateau