because... not many people use Google+?
sorry.
sorry.
In my opinion the reach of Google, and therefore their ability to cause harm, is even greater than Facebook's, and beyond the veneer of perceived benevolence they are just as unethical.
It's also quite possible that people aren't aware of critisism against Google simply because Google chooses to hide it. They're that powerful right now.
But Youtube's MUA is, IIRC, above Facebook's. That's Google's real social app.