Earlier quoted context omitted.
In that parallel universe web sites stop publishing RSS because they are overwhelmed with the polling traffic. The world really does need something like ActivityPub as much as Dave Winer denies it. RSS has two polling speeds: too fast and too slow and it can even be both at the same time.
There are rss aggregators that poll every feed occasionally, then combine them into a single feed for each person to consume. Nostr works on a similar basis but you push to the aggregator instead of them pulling.
It costs me 10 cents/(month*feed) for superfeedr to ingest an RSS feed; it fills up an SQS queue with content items which is a model I find easy because I can drain that queue at my leisure.
It would be very cost effective for me to add a Planet and have my recommender system discover articles I like from it, that is, I'm happy to ingest 1000s of items a day to my reader.