Realistically, what was the benefit of the ad-driven model? From my point of view, most of the highly-valuable information came from the various forums, wikis and personal sites, on all of which people would publish the information for free. Ads were largely used to cover hosting costs of the large forums and wikis, but the content creators saw not a single dime.
Over the last 15 years, the search results have shifted from this, to instead become 100% news articles and SEO spam, all with a lot of fluff and very little substance, tons of ads, pop-ups, autoplay videos and subscription walls. All of this is well funded thanks to the business model, but for what? I can't imagine anyone sitting through all that crap to get to what they were looking for. There's a reason people would tell others to add "reddit" to the search query only a few years back, and even that's becoming less worthwhile.
Is this really what we want to preserve? Big publications and their interests?