a factor not apparent in your thinking is the question of demographics. All people might well be a suitable metric for Nike. But it’s a very wasteful idea for very many others. Especially when the web makes that universal.
AdSense naturally drives prices to zero because despite the “metrics” it’s impossible to know with any certainty who’s looking. Media that rely on open metrics inevitably head towards cheap, nasty ways to drive “traffic” which themselves accentuate the demographic failings.
Pricing content actually helps discriminate and raises relevance and almost certainly justifies higher CPM.
Of course, nothing wilo save those whose content is irrelevant.