While Barbara Hambly is no futurist, she nailed this one in Knight of the Demon Queen. She portrayed a slightly more technologically advanced alternate universe in which people have ads playing all around them all the time in order to offset their living costs. Only the well-off can afford to have anything resembling privacy by disallowing advertising.
For the medieval-world character who gets temporarily stuck there, it’s a version of hell. And it appears to be coming to our future. Ain’t technology grand? Remember: at Google their product is you.