Google is about to do something that will make the mobile viewing experience all that much better: the removal of pop-ups and interstitials. Most readers would say that these ads make the viewing experience much worse. Google is making the call to worsen the search results of websites that use interstitials and pop-ups so that they rank lower and therefore get fewer hits.
When it comes to ranking on Google, there a ton of things that go into why a certain website will rank where it does. It isn't like every website that uses these ads will have to immediately change what they do, especially if the website ranks highly by a large margin. Still, this change may benefit a few sites if they are competing for spots with equal websites.
Google's intention is that they want to get people more information but to keep that information handy - for example, you don't want them to be annoyed with a pop-up. Google has been working on this for years with their traditional results, but last year it began doing so for "mobile friendly" websites as well.
They've done the same for encryption. Not all websites offer mobile sites nor do most websites offer encryption. Still, these websites have no choice but to listen to Google because search rankings are the way people visit a website. Following these little nudges are the way that websites make their money.
There will be time to enact these changes, as they go into effect on January 10, 2017, according to The Verge.
There are some ads that are still okay. Google is looking for content that will prevent you from reading a website - whether you have to wait or you have to hit an X. Not all pop-ups and overlays will be included. Pop-ups will need to meet legal requirements like verifying someone's age.