People browsing habits are changing.
Before all that social media platforms appeared, people were visiting pages most of the time. At most, some of us were using RSS feeds so we just go sites when there was something interesting.
In nowadays situation, people are mainly on social media platforms. In those social media platforms they get what they are more interested in. Many people like just to visit a page because that friend recommended it. A recomendation from something you really -or maybe no- know is more valuable than a recommendation from an ad or a search engine result.
They have getting used to ads in social media platforms and, tend to get blind of them. So that is the reason I think people are stopping from browsing websites and just visiting pages they were recommended.
That also means, of course, that someone has to visit those pages so they can recommend them. But traffic is much more low.
I use feedly to read a lot of blogs, so I don't see many ads. Otherwise I either block them or ignore them.