People see "targeted advertising" as "I was thinking about buying a bike and it shows me ads for bikes", ie. it's showing me what I want to see. That is not targeted advertising. Targeted advertising is showing you what they want you to see when they want you to see it, or showing you the same products in a light that makes you more likely to buy them.
For example, showing you unlikely or imagined bike-related problems, to sell you useless protection gear or insurance after you get your bike. Showing you ads for motorcycles, because although you probably don't want one, someone who already likes bikes is more likely to buy a (more expensive) motorcycle, so that's where they'll direct their spam.
Targeted advertising is about manipulation, using knowledge of the customer to change their behavior. No one is going through those efforts to show you what you already want and save you a quick Google.
you have quite a low view of people's ability to make decisions for themselves if you think being shown ads is manipulation. And I struggle to see how targeted ads are somehow worse than the same sort of 'manipulation' inherent in using an algorithmic feed like HackerNews or Twitter. Both are exposing you to things they want you to see. Yet you don't seem to have such strong opposition to those as you do targeted ads.
I think it's less the targeted advertising, and more like I can't take 5 internet steps today without 40 people shouting at me to buy their diapers because my partner googled "diapers" last night.
Two because the ads are more relevant the advertiser makes far more money on them and therefore doesn't have to show you as many to fund their service.
For example, showing you unlikely or imagined bike-related problems, to sell you useless protection gear or insurance after you get your bike. Showing you ads for motorcycles, because although you probably don't want one, someone who already likes bikes is more likely to buy a (more expensive) motorcycle, so that's where they'll direct their spam.
Targeted advertising is about manipulation, using knowledge of the customer to change their behavior. No one is going through those efforts to show you what you already want and save you a quick Google.