I guess I also fit into that crowd who misses forums. I only managed to experience the very end of them before the Discord singularity hit the Internet, but have through personal research some shallow retrospective knowledge about how the Internet was before I was here.

The Discordification of the Internet has generally been a disaster. It expands beyond more than just Discord, like Telegram groups which are also somewhat underground, inaccessible, hush-hush places that you end up needing to know someone to know it exists and then know someone else who can invite you. But then you end up finding one of those from Reddit and you realise that the local furry group you heard rumours of is mostly inactive because most people just don't have time to socialise anymore. The shift and why things have become the way they have is complicated and not just "forum -> discord = misery".

Public Discord servers with thousands of members will just make you drown into the noise, and ever since a couple months some of those I used to be in have slipped and slided into nazi bars and I've ended up just removing myself from them.

In contrast, smaller forums end up being open spaces accessible and inclusive to guests and lurkers to discover and browse it before, without the pressure of getting flooded with welcome stickers when you join a Discord server/Telegram group. Generally calm and you can take some time to come back and respond. You'll of course have the effect of all posts being public, and even though Discord is definitively not private people will have the perception of privacy there anyway. A public/private forum section duality somewhat helps with that I guess. And what you need to do to foster a healthy community and the kinds of anti-social behaviour you need to keep out before it rots the community from the inside doesn't really change.

IMO every single Discord or Telegram group would have been a forum 10-15-20-whatever years ago, probably with an IRC channel to go with it. And things would probably have been much better if that were still the case today. Or that's at least what I think when I roam the Internet and see abandoned local forums and communities through Wayback captures and other historical archives and see everything I have missed.

An active and friendly retro forum culture in the modern day would be great, but it usually just ends up where you drag people off Discord to have a little tea play party with plushies and then you go back after a while. I've been meaning to set up a local forum in my native language and see if anyone shows up, but I'm not having any particularly high hopes for it so I've kinda dragged my feet on it.