Exactly this (that people want it at least - I don't think that means it needs to exist). And I think there would be a lot less frustration in the discourse of ActivityPub vs. ATproto, if we could collectively agree that you can't get this in a decentralized system. In a dense network, the number of edges scales with the square of the number of nodes. It's just not feasible to have a network that is both dense and has a large number of nodes.
I think "I prioritize virality, recommendation engines and network density, thus accept giving control over the network to a centralized and profit-oriented entity" is an entirely reasonable tradeoff to make. I just don't understand why BlueSky users don't seem to accept that it's the tradeoff they are making.
Bluesky's architecture was pretty much dictated by the premise that anyone needs to be able to see any post on the entire system, regardless of whether they have any connections with the author. That algorithmic entertainment-style feeds need to exist. You do need that firehose and other expensive infrastructure for that, there's no going around it.
The fediverse, on the other hand, entirely relies on people following each other. Each server only receives and stores data that is relevant to its users. ActivityPub works like an automated email list management system. You follow someone, they start sending you their updates and forwarding any updates from others that they consider relevant, like replies to their posts.