> I hate the ad-centered nature of modern web anyway, but I don't understand why ads are not based on the content of a webpage/video.
This is because tracking data is google's moat.
They don't want people to offer content-based ads. Why? Because they will find out that they work pretty well while preserving privacy. And will start using them. But then Google has a problem, because to offer those you don't need a global pervasive tracking network to do it. Anyone with a few million can set up an ad network and compete with Google.
So, they try to double down on their tracking driven approach because it's something only they and a few other big ones can do. Content-driven ads they discourage with propaganda that they don't work, just not offering or making them difficult to use.
