Google is not alone in using dark patterns -- Facebook got tons of growth by using dark patterns around privacy. Google is copying that strategy a few years too late. The age-groups that are leaving Facebook are doing so b/c they understand the dark pattern maze for what it is and don't want to deal with it.
Nobody leaves Facebook, it is just used differently. That's a big detail that only a few articles seem to get correct. Kids are still on Facebook, with grandma and mom and dad, but they also have a Tumblr account.