The only obvious ad I've ever clicked on was for a "free" IQ test. I figured I'd never done one cause they're fake, but I had time to kill, so I clicked through. After 20 mins or so answering questions, it ended on a transaction page. The only way to see your "results" was by paying $20. I obviously didn't pay, and instead tried to report the ad, only to discover that Google Ads has zero mechanism to even report scams to Google. After some research, it turned out that this blatant bait and switch scam had been operating via Google Ads for like 5 or 7 years. Google doesn't give a fuck if scammers use it's ad tech to scam your grandma or inject your system with malware, as long as they get paid for the privilege.
I've always used an ad blocker, but the whole experience reinforced how anti-consumer and pro-criminal surveillance capitalism is. Permanent absolute ad block — without exceptions — is how everyone should operate, because none of these companies deserve any trust whatsoever. Even if you trust the site you're visiting, you can't trust any ad company they utilize.