I could imagine that blocking bot traffic, would improve their retargeting and make sure that the retargeting budget is spent on real people leading to an increase in conversion.
What's the API here for Google Ads? How does their site report to Google Ads whether that was a good/bad user?
Is this done through conversion tracking? If so, why would you track anything but a completed purchase in the first place?
I think Google calls it remarketing and it goes through Google Tag Manager. You can "tag" visitors how you want (duration, action, page scroll, etc.). It's just a javascript call to the API which you can trigger however you like.
You wouldn't necessarily want to track conversions for retargeting, since depending on your product or service, a second buy might be unlikely. But someone who checks out multiple product pages or articles on your site might be interested and buy in the near future. That of course are also actions bots could easily do.
