Okay, here's a crazy idea for advertisers. Tie the advertisement to the type of content that the user is already there to read about. Then you can serve ads from the content web server and make it indistinguishable from content, completely unobtrusive, completely noninvasive, and maybe even welcome.
This. As a positive example, I like how many YouTube channels take 30 seconds out of a 10 minute video to talk about some company's product that might be of interest to their audience. Not an annoying video ad that has nothing to do with what I'm reading / watching, just the host talking about a product or service that their audience has a chance to be interested in.
I like how many podcasts have ads with predictable lengths, so I can skip them with the "fast forward" button without hearing them. NPR is 4 skips; Slate is 8-10. It seems like "deep learning" should have figured this out by now.