Each had a unique set of pitfalls. Out of the 3 Usenet seems to be functionally dead for it's original purpose. Perhaps there was no possible outcome where usenet would scale along with the internet.
The email spam issue is trivially solvable with a contact whitelist, which is a UI issue. Email as it is right now is definitely very usable, but keep me the hell away from anything from Microsoft.
IRC is alive and small. On the optimistic side it outlived Skype. Maybe 25 years from now IRC will still be working and Discord will be dead. There has been a lot of buy in on Matrix, but I'm unconvinced the protocol is going to thrive long term due to design choices made.
Reddit is doing what Usenet did. In my ideal world, reddit would be part of the fediverse along with Usenet & Twitter and the UI would close to hn.
I’m obviously biased (as proj lead for Matrix) but I genuinely think Matrix is in a good place going forwards. There’s a lot of legitimate complaints about the transition to Matrix 2.0, and trust & safety still needs a tonne of work - but the core protocol and featureset feels pretty good. Critically, we just showed we can successfully land pretty major changes to the core federation protocol to improve it (https://matrix.org/blog/2025/08/project-hydra-improving-stat...), which feels pretty liberating in terms of having carte blanche to fix the other remaining warts.
What design choices are you worried about? (To confirm that they are on the radar).