It will be a cat and mouse game, which YouTube will loose in the long run. Don’t remember the name, but there is a very clever solution: They download all the ads so YT thinks you are watching. However, ads are never shown to you. This is extremely hard to detect and it muddies the data collection of Google since you watch and click everything.
IMO: This is a net loss for YT/Google. Their collection of data looses value. And advertisers wont be willing to pay the same amount for clicks, since a registered click is not necessary someone who watched and the targetting got worse…