Because “personal responsibility” only goes so far. It doesn’t account for how people in a society actually interact.
If your friend doesn’t jump through all of this month’s hoops in BigCorp’s shiny new privacy policy (so lazy for not opting out yet again!) then your privacy might become collateral damage.
My personal opinion is that framing problems as personal responsibility rather than collective action is a conspiracy to stunt actual solutions. It is effective because it shifts blame from offending companies to unknowing individuals.