Smoking is an interesting example because the negative effects aren't just confined to the individual. Smoking a cigarette is the atmospheric equivalent of peeing in the pool except it also causes cancer and other health issues. Maybe it's actually an
important example because it's an undeniable illustration of 2nd order effects, which are less pronounced in other cases but probably still exist.
And "any room for personal responsibility"? There are plenty of domains of behavior that aren't regulated; there's a whole world of choices individuals are responsible for alone.
Various forms of regulation regarding smoking, seat belts, and yes, even raw milk are all working in areas where limited human capacity for evaluating risk meets deadly consequences. Privacy is arguably different since it's unlikely to be directly deadly, but it does meet risk evaluation limits and adds in that incentives of 3rd parties are against individual incentives, and many of those 3rd parties have incredible resources available to them in order to obscure behavior and subvert protections. A collective response is a reasonable one.