There's no reason that ads today couldn't return to that regime. Contextual ads operate without surveillance, using the same "real-time bidding" mechanism to place ads based on the content of the article and some basic parameters about the user (rough location based on IP address, time of day, device type):
https://pluralistic.net/2020/08/05/behavioral-v-contextual/#contextual-ads
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Context ads perform about as well as behavioral ads - but they have a radically different power-structure. No media company will ever know as much about a given user as an ad-tech giant practicing dragnet surveillance and buying purchase, location and finance data from data-brokers. But no ad-tech giant knows as much about the context and content of an article as the media company that published it.
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