[ancymon]

I think one of the reasons for user tracking is fraud detection. The moment you get rid off it, nobody would be willing to "risk" advertising on smaller, unknown websites. So maybe such ban would make monetization for small publishers much harder.

[Nextgrid]

Fraud is only a problem for advertisements based on CPM/CPC. Time-based advertisements (pay X to have your ad displayed here for Y time) tracked by overall purchases (using an unique link) don't have a "fraud" problem given that the only way to boost the ad's effectiveness is to literally buy the product multiple times and pay for it.