[brtt]

Who is the hypothetical you in the second to last paragraph? You are assuming one scenario, that of a brand or agency planner, who is creating a media plan with audience builder or w/e the name is these days.

Saying or assuming that no tech companies sell user data is disingenuous. Case in point, doesn't Edmunds have an exclusive data contract to share data with Oracle Data Cloud?

[edmundsauto]

An advertiser, in the 2nd to last paragraph. I'm only assuming the facts in evidence -- that FB and Google aren't selling user data. They sell advertisements, which use user data for targeting via generally broad mechanisms or 1st party data.

Re-reading my comment, I don't think I said anything about companies in general.