[Nutmog]

Isn't the data gathering an improvement on efficiency, not a reduction of it? If you define efficiency as something like a ratio of useful informing to viewer attention. More personalized ads should be providing more useful information with less noise from irrelevant information. Your example of TV is a good one to show the value of targeted ads. TV ads are even more wasteful of people's attention.

[Joof]

Depends on your perspective. I try to stay the hell away from ads (ads are generally not a good method to discern how to think or buy things) and don't buy all that much anyway; the ideal personalization for me is ads that are in-depth and provide a neutral comparison among products I already want. So basically, no ads; I'll find what I'm looking for.

Since I have no interest in ads, targeted ads are worse because now my data is out there too.

From the perspective of a company, targeted ads probably make more money than untargeted ads, which make more money than zero ads. It's a compromise to try to get those who have zero ads to move to untargeted ads.