The problem with the idealism of targeted advertising is that it assumes that there is always an ad that fits your desires. In reality, some people have very niche interests and preferences, and not every business advertises through the same channels or with the same budget. Ads will pretty much always cater to the lowest common denominator even if you account for the individual.

Search ads do seem like the one ad type that kind of flips that though. Where it's not based on some general set of interests, but literally the thing you're searching for at that moment.