i’ve been thinking about this for a few years now. my two cents.
ad models stop scaling with the gorwth of decentralized social protocols because no centralized entity exists to coordinate their delivery. inventory, algorithms, personalization, or even the chrome where these ads are served.
the economics are also bad. byte dance makes 50b$ plus every year but their creator fund is 200mm. spotify paid snoop dog 40k for 1B streams.
the main way to make money (and my bet) will be enabling creators to connect / monetize / build community directly with their audience rather than get disintermediated by the likes of meta and tiktok.
these will likely need to happen on different app views (web/mobile) for different nodes.
activity pub has very poor support to coordinate something at scale and build in a consistent way - something i think @atproto does very well.
i imagine meta has decided to answer the question of how to serve ads in an increasingly decentralized world and still be in control - but this may be harder than anyone thinks?