I draw the exact opposite conclusion.
It would drive traffic to the sites with the best content—the more niche the content, the more suitable the advertising. Perfect for smaller publishers.
I look at it from the perspective of the advertiser. They’d buy ads via a small set of big sites (with better targeting data and infrastructure) rather than do deals with millions of small sites. I don’t see how the shift in traffic would happen despite this.
But why would that change if the advertising were contextual instead of behavioural? The brokers wouldn’t change, just the algorithm that decides which ad to show. adactio.com/notes/17673