[0]https://www.wired.com/story/bots-online-advertising/ [1]https://www.marketingprofs.com/charts/2010/3485/us-ad-spend-down-123-in-2009
In the early days of web advertising, there was a lot of noise about how it was all a scam and no actual human ever clicked on a banner ad. Yet you still see banner ads three decades later.
Companies have marketing budgets and the people making those decisions are not universally incompetent. Marketing budgets have existed for centuries.
But assuming your premise is true and the value of hyperpersonalized ads drop significantly, which parts of the tech industry survive? All of them. A specialized business that's very dependent might fail, and big players like Facebook or Google might falter. (Facebook might not be able to fund their metaverse projects for example). The resulting landscape would be consolidated and boring, like radio. And the exciting growth would come from somewhere else.
Also, why are these stories making the rounds again? Did something actually change in the industry?
For sites and services that had a successful business being ad supported, when that becomes unsuccessful, there's likely to be a lot of consolidation: if the consolidated entity is large enough to run their own ad network, they may be able to make the economics work a bit better.
You'll also see some of them try directly charging users or soliciting voluntary payments.