There is a pretty big difference between a legitimate ad and what Google is saying they are targeting here. We can't be sure if Google will end up targeting other ad companies in inappropriate ways - but we can remain vigilant. However, whats actually been announced here is that they are going after garbage ads that in my anecdotal experience, are basically 100% malware / scams and its a complete fallacy to say that Google should not do something good (shut down that garbage) because they _might_ later do something bad (which they could do regardless of if they shut down that garbage).
I'd challenge anyone to provide even anecdotal experience of encountering an ad that meets their stated guidelines for being an abusive ad (linked by Yver at: https://support.google.com/webtools/answer/7347327) that isn't a scam / malware.
You clearly don't understand what google is proposing at all.
They are going to block all ads on a PUBLISHER which shows any of their list of bad ads. This has nothing to do with ad companies.
My point is that google has -- including relatively recently! -- quite proudly run the ads they label as bad ads, which now trigger blocking of all ads on the site, on google.com. And there will be future instances of malware ads on google.com. See: malware and unwanted software, particularly for downloads such as vlc or flash.
So when a publisher has a stray bad ad on their site -- an no one is disputing these ads are bad -- google is going to screw them. When google doesn't blacklist scam software install ads, or whatever slips through their filters, well, what can you do? No chance chrome blocks all ads on google.
