I don't think there is a solution. The internet as we knew it is over, I give it 5 more years before it becomes borderline impossible to find new human-created content on it.
Incentives will make sure that this new web will become the old one given enough time.
The only reason there's a connection between the richness of the content, and the likelihood of it being an ad, is because advertisers attract attention by making things shiny. But if we short circuit that upstream, by not running untrusted js to begin with , then there's no reason that we can't have shiny content downstream of where the trust was verified.
Information doesn't need to be shiny.
If the platform can show shiny content, then ads WILL FIND A WAY.
I've never been served an ad over bittorrent, for instance, because it only gives me what I ask for and I only ask for things that are trusted by my peers. The ad problem is structural. If we change the structure, we change it too.