In order to understand this, we need to explain the "Adpocalypse" - a thing that happened to YouTubers and, more generally, online content publishers that sell ads through Google. More generally we need to talk about the changes that advertisers have made with respect to how they think about brand association.

The way advertising companies used to treat online advertising a decade ago was that it didn't matter where your ads were placed, as long as they were going in front of people who were interested in them. That's why you had large ad exchanges with third-party tracking tools to build up behavioral profiles, because it was the best approach for linking advertisers and publishers. Publishers generally didn't care about who was advertising on their pages and advertisers generally didn't care about what pages their ads wound up on. This is, of course, a generality; there's always been picky advertisers and/or publishers, but the core point remains: the business worked because inventory was fungible.

And then advertisers realized that their ads were showing up on videos of Klu Klux Klan rallies and other far-right nonsense.

Well, they didn't so much realize, as much as they were publicly embarrassed when journalists started writing news stories about it. Consequently, you saw multiple waves of brands making a show of pulling all their advertising until exchanges implemented better controls for brand association and advertiser safety. Of course, this means that exchanges wound up over-enforcing ad safety, constantly harassing publishers that might be on the line. Journalistic outfits were unusually impacted, because their content is rarely advertiser friendly, even though they're not the right-wing nutters that started this mess.

This problem isn't related to trying to keep right-wingers out of ad money, though. There's a sort of converse Adpocalypse that happened to publishers, called malvertising. This can take many forms - from fake popups for scam tech support companies, to just outright dropping a zero-day exploit on your victim. This causes reputational problems for publishers, since safe-browing services will flag your site (basically making it unusable without lots of scary warnings, and heavily punishing it in search engines) if it starts dropping drive-by downloads on users.

So, advertisers are unhappy because of bad publishers, and publishers are unhappy because of bad advertisers. What about the users? Well, they're installing ad blockers in record numbers because they don't want to get hacked by malicious ads. Also, many of them aren't actual users; the online advertising business has had click fraud problems way before malvertising or brands getting cold feet over what content they're paired with. That's actually part and parcel of why online advertising is so tracking-heavy; it lets them detect the difference between an actual reader and someone just clicking on their own ads all day to defraud advertisers. Guess what? Users don't like ad tracking all that much either (especially when exchanges are so directly in-your-face about it.)

In any fungible market, the presence of "bad" commodities drives out "good" ones. What you have now is a toxic market, one that Google more or less owns outright because everyone else has been driven out of business or acquired. Google isn't the cause of the toxicity, but they benefit from it regardless, since Search display advertising will remain brand- and user-safe in ways publisher advertising isn't. In this new market of TV-like, non-fungible advertising; Google is no longer a business partner. They are a hostile, dogged competitor paying them ever-shrinking table scraps.