How do algorithmic feeds work in the fediverse? Are there already services out there the last slurp in a ton of activitypub feed data and help surface content to users that they will enjoy? Some of the centralized social media services do this extremely well after you've been using them for awhile (YouTube in particular)
That being said, you can overlay some semblance of algorithmic feed in the client that presents the Inbox contents to the end-user, but that is not related to the specification in any way.