Oddbean new post about login | logout agree. my original point was more that there's no good that can come from a centralised system that can profile its users so effectively...
I think I would say that there is good (it can book holidays or reply to emails for you), but the potential bad could significantly outweigh the goods. We've always made our own decisions about that balance. Facebook, the previous system that knew you pretty well could deliver content you enjoy and suggest things you like, but then Cambridge Analytics showed us the dark side of this.