Nostalgia makes everything look better than it was. The reason the internet worked then was because it excluded most people and the few people that were on it had a lot in common (like being young and early adopters of tech stuff and into a lot of immature crap). Holding up a mirror to myself here.
The point is that this never scaled and it started to break down almost immediately as more people started showing up. The moment Facebook broke for me was when I realized my mother, aunts, distant cousins, etc. were seeing absolutely everything I posted there and would be gossiping about it endlessly. Same with linkedin. Fun informal way to keep track of old colleagues and pimp your CV. But then everybody you ever reported to started showing up, and their secretaries, and that annoying guy that you never liked. And it became a cesspool of marketing drivel, up-beat management cliches, and worse. So, I disengaged there as well.
The old internet was only fun because most of those people weren't there yet. It had nothing to do with the technology. The technology was mostly not that great actually. RSS was a bit of a dumpster fire if you ever had to deal with parsing that. It was all a bit hand wavy. Titles go there but sometimes they go there. Dates might be iso timestamps. Sort of. Maybe. Sometimes. But definitely not always. Nominally XML but not guaranteed to be valid XML.
As a standard, it's pretty crap and hand wavy. But it was simple enough that you could make it work anyway and there was enough RSS out there that it was worth trying to parse and make sense of most of it, deal with the encoding issues, try to normalize the timestamps, etc. And do useful things with it (aggregating, pinging, linking bag, and all the other wonderful stuff people did).
The tech was just a (very limited) enabler. What made it work was the relatively homogeneous groups of people using that stuff.
That can still work. But it's not really technology dependent. Without people you have an empty room. Empty rooms are boring. Solving the empty room problem is the key thing. How do you get the right people to show up?
You're right, issue imo. With the web is that once 1 competitor gains traction then everyone else folds over time.
I remember gametrailers.com, quirky little site for hosting game related content, it folded once YouTube was the platform for commercial video uploading.