People were generally pretty irritated (as was the public) by the integration of every Google product into it. Leadership (both internally and externally) was pretty clear that it was meant to be a platform, one that unified all of Google's products with a shared social layer.

I worked in research at the time and have never been a heavy social media user, so it didn't really affect me much, but the internal story seems to fit reality more than what you're describing: the change in user facing functionality was progressive integration of Google products (like YouTube)