This is a tricky proposition. Google has free speech rights to display whatever they want on their own server pages. These aren't statements of fact so it's not

This is a tricky proposition. Google has free speech rights to display whatever they want on their own server pages. These aren't statements of fact so it's not falling under libel & co. It's like saying that you want to regulate what can advertising companies display on billboards, ex. they cannot display competitor's ads nearby your company's offices. Since the billboard space is private and owned by the ad company (similarly to the ad space on Google servers served pages), they get too decide to put there whatever they want (barring free speech limiting regulations).