Google's AdSpam/fraud/bot-prevention team was, when I worked there, world class and fairly well funded, took their job seriously, and had access to all the data. It's an existential threat to the ad business, because if Google gets a reputation for being full of bots/spam, then the advertisers will bid lower per click/conversion to compensate, which means that legitimate website publishers will get paid less and go to other networks, which is a feedback loop that leads to the entire market collapsing (see also: https://en.wikipedia.org/wiki/The_Market_for_Lemons). It's absolutely worth refunding/zero-rating huge amounts of advertiser spend to avoid that situation, and they do.

It's not that they're not trying, it's just a very hard problem.

it's also just flat-out unsexy from a product/MBA-brained perspective to push for something that will negatively impact metrics for your users. I ran into this when I was advocating for onboarding a third-party provider that would filter out automated/spambot email clicks thus decreasing the north star metrics our users had for engagement (even though it was truthier and would provide more accurate targeting and some of our most senior people had been advocating for for years)

the only reason I got the go-ahead for the effort was because one of our upstart competitors who was handily eating our lunch had implemented this years ago, started advertising based on it, literally pointed to the fact that we didn't do this yet, and then this was followed quickly by all of our other competitors implementing this, too. at this point we were well inducted into the illustrious halls of companies who stopped giving a shit about their core product with leadership blaming everyone but themselves for the fact that we were churning faster than we were net-new-ing

and even then it was a half-assed, resource-starved implementation that got dumped on regularly. have left the org since and couldn't be happier

Alphabet has claimed to be fighting ad fraud for many many years.

That is not how an organization fighting ad fraud would structure itself.

Alphabet does not have an abundance of technical incompetence. But it does have the strongest of incentives to ensure ad budgets get spent quickly and no meaningful disincentives.

I mean what’s the OP going to do, go to Google’s competition?

I mean if you could show Google know they're charging people for ads they're knowingly showing to robots then a few €Billion of fines for fraud should be following.