... but if you have any ideas they haven't tried, I suspect they'd love to hear about it in a job interview for any of the openings for ad quality SWE.
I think this really requires governments to step in. I mean one could easily argue that Google is facilitating fraud here, so maybe they should be liable?
Toxic waste doesn't try and hide from the litmus paper or the geiger counter.
There is no reason they have to serve 30 billion impressions a day. If vetting takes that down to 1 billion, that's fine. Lower the volumes (and raise the prices to fund manual vetting) until the problem is resolved.
Toxic waste disposal is a solved problem thanks to (enforced!) regulations that force companies to do so under threat of heavy penalties, not altruism or the fact that the waste doesn't hide from a Geiger counter. We need the same for online advertising.
But even if we accept that there is a downside, it's clearly not enough because this problem keeps happening again and again. Whatever downside there is needs to be increased by a few orders of magnitude for them to take the problem seriously.
The malware continuing to appear isn't sufficient evidence. Malware moves hosts and ad accounts all the time.
ETA: from the article itself, in 2021 Google "Removed over 3.4 billion ads, restricted over 5.7 billion ads and suspended over 5.6 million advertiser accounts." That's a ton of action, but AdWords alone also serves 29 billion ad impressions a day. It doesn't take more than a few bad actors slipping through the cracks to get seen (and at these orders of magnitude, "a few" is still "millions." Completely impractical for human hand-review).
It's clear this will never be prioritized without regulation as scammers money is as good as anyone else's and open source projects cannot afford to sue Google to force action.