All advertisers wouldn't be together converging on the tracking-based ad model if that were the case. It's being used because it's driving more CTR than the traditional way.
Your browsing history gives a more reliable base to segment you based on buyer profiles (incl age groups, location, interests), figure out your "intent" and target ads based on it. If you were to, say, read a random "Top 10 cars with highest resale value" article, on its own without historical data it won't be of any use for targeting because they don't know if you're actually a potential buyer in the market or just some teenager passing their time. Showing you those ads will waste their $$ if it were the latter.
This isn't in any way an endorsement of their intrusive advertising practices, by the way - I personally have been using ad blockers and aggressively taking every step possible to avoid all online advertisements for more than a decade. It's just to provide a perspective on why it's not so simple.
Your browsing history gives a more reliable base to segment you based on buyer profiles (incl age groups, location, interests), figure out your "intent" and target ads based on it. If you were to, say, read a random "Top 10 cars with highest resale value" article, on its own without historical data it won't be of any use for targeting because they don't know if you're actually a potential buyer in the market or just some teenager passing their time. Showing you those ads will waste their $$ if it were the latter.
This isn't in any way an endorsement of their intrusive advertising practices, by the way - I personally have been using ad blockers and aggressively taking every step possible to avoid all online advertisements for more than a decade. It's just to provide a perspective on why it's not so simple.