Neal Stephenson explores something like your “user agent” idea and comes up with an different solution in his novel “ Fall; or, Dodge in Hell.”

Spoilers ahead:

In Stephenson‘s world people can hire “editors” to curate what they see, and those editors effectively determine reality for people at a mass scale. This is just one of the many fascinating ideas Stephenson explores and I highly recommend reading the book.

This interview covers some of the details if you’re not willing to dive into an 800+ page novel:

https://www.pcmag.com/news/neal-stephenson-explains-his-visi...