It could very easily happen, by enforcing blocking rules that restrict or eliminate third party content.
That won't work. Even if you don't communicate directly with the third party, you don't have any way to prevent the content provider (who is also the ad provider from your point of view) from passing the information along.
We seem to have latched onto this "third party content" as The Problem, where it's really just a hack du jour for easily spotting a problem. But the only reason a content provider is putting <script src="somewhere else"> into their pages is because it still gets them paid by the "somewhere else." If you hit their own server instead of the third party, they can still forward any requests behind the scenes to anyone, and you won't even know it's happening, but all the same information will be there.
If you eliminate "third party content" you're just going to turn second parties into proxies. And they'll really do it, too. Why wouldn't they?