Chrome has a responsibility not just to the end user but also to the website. The cost of the getting the web page's info was viewing the ads. Why should the browser help the user to commit virtual theft?
Simply blanket dismissing ads as "tenuous position" is nonsense. Lots of people make a living via web ads. Google makes billions on ads. It's a real source of real money. Alternatives could, and should!, be considered. But simply cutting off a revenue stream while arguing that the ability to cut off that revenue stream should be protected by regulators is weak at best.