But like, the front page you and I each see on Hacker News is the same, the comments we see are the same, and everything is in the same order; if we talk to each other about trends in posts on Hacker News, we have some basis of shared reality.

Is this everyone? No. But "forcing one shared experience on everyone" is a straw man that wasn't being argued: the argument is about the other extreme, where every user has their own feed, and worlds splinter so hard that they are inherently irreconcilable with anyone else's.

I appreciate your viewpoint here, and the sibling comment also. However, how does one practically not get an extreme version where everyone has their own feed. Speaking very personally -- here are my interests:

photography, brooklyn, coffee, health-tech, health-ai, fin-tech, finance, quant, bears, cats, calico cats, ucberkeley stats alums, genai in marketing, generative-ai created music, east coast gangster rap

There is no one community for all these. There are not even individual communities for each of these, some are too specific.

Yes, there are random slack instances (e.g., for ucberkely dept alumni) and random boards (quants and poets for finance) but social media provides a giant funnel for everything and hashtags let me focus on long-tail items of interest. I've carefully curated my account follows and hashtag follows over years.

First off, when you manually curate your world, you know what you chose to curate it for and you have to be are well aware of the world outside of it: it doesn't all automatically just happen in a way that can trick you into believing the entire world might be into your niche interests.

But also, looking at this as a kind of fractal level of curation, even within your east coast gangster rap community, there are still going to be a variety of people who think a number of different things about the world at large; and, unless you have an algorithmic feed inside of that community, you will see those varied models of the world blossom.

What happens when you fully go down the algorithmic feed rabbit hole is that, if someone in east coast gangster rap disagrees with you on some other unrelated axis--or they are simply boring to you--they will get increasingly filtered away by the algorithm, leaving you alone in your misleadingly-cacophonous bubble.

There’s an optimal middle ground and physical real world communities built around a shared interest generally fit this well- you still get a diversity of people, but they all want to be together for a reason.