I run wireguard on an OVH box that I've had for years as my VPN. I just checked and I still get Google ads.

So it's not even automatic on the largest ads network out there.

Personally, I'd love it if using a VPN meant that advertisers didn't even try serving ads to me, but unfortunately that's not the case.

What, you just expect Google to show you a giant red box saying "Whoops, we detected that you were trying to do an ad fraud! Better luck next time!". Google will happily show you whatever ads you request, but they won't count them as monetizable impressions and they won't charge advertisers for them. The goal is to make it impossible to tell as a bot operator whether your fraud was successful. So why give bot operators more info about how to evade your detections?

They should not charge people for them but they definitely do.

I mean yeah but Google doesn't count those clicks for ad revenue at all

or maybe just on OVH or smaller provider,but AWS ips are definitely flagged for advertising