@donaldball @baldur Honestly, it's probably a lot simpler: the only way to differentiate yourself as a new advertising broker is to claim to have data that your competitors don't, and so it's in the direct financial interest for adtech companies (including but definitely not limited to Google) to insist that behavioural advertising is not only effective, but *crucial*.

Because if you can't convince advertisers of that, you don't have a business; you can't get fat profit margins from brokering commodity contextual advertising spots, because anyone can offer those, so you have to invent some special sauce that justifies your existence and cut, whether it really exists or not.