Was it easier, 10 years ago, to make money from a website, with just one single (non-animated) banner on top, than it is today with a website that's plastered with animated banners, link ads, and other stuff?
Was it easier, 10 years ago, to make money from a video platform, with just one single skip-able ad at the start of each video - than it is today with 10 un-skip-able ads in front of each video?
Was it easier to advertise your business 100 years ago, with a single poster on a street corner - than it is today with a huge ad-campaign consisting of TV-, Radio- and Newspaper-Ads?
The big question to me is: Does advertising become less and less effective the more people are exposed to advertisements?
Advertisers are measuring the actual effectiveness of their ads, and paying for that only. Therefore falling effectiveness means falling prices and you have to increase the quantity of ads, to earn the same money (and achieve the same effect) as before.
But increased quantity means people are exposed to even more ads, which means they become even less effective. Which leads to even lower prices and even higher quantity.
This can't go on forever... at some point the loss of effectiveness is going to be larger than what you can possibly make up for by increasing quantity. And there's an upper limit - you can't push quantity above 60 minutes of ads per hour.
This can only end with all users either signing up for premium, leaving the service all-together, or using ad-blockers. In all three cases, the ad-business looses.
Are we witnessing the slow death of (online) advertising?