Thread support was added to alleviate some of the noise problem but in communities that actually use them there's so many threads it's easy to lose track and everywhere else they're basically just strange ways of isolating yourself from the rest of the people in the community.
I stepped away and came back like a month later.
It had grown so fast, with so many users, there were suddenly like 50-60 channels, it was unreal how hard it was to keep track of anything happening. Even the original three channels were completely overrun with so many discussions and chats, I couldn't keep track.
So I had the experience of joining a small server, only to have it blow up when I came back and I just had to give up and moved on.
None of this scales, it's totally unworkable if you have 100+ people actively chatting, let alone thousands.
I never would have found the smaller servers, where at this point no one's playing the game we initially met through but are all friends, if not for bigger servers meeting the need of that entrance to the pipeline.
Reddit is/was also arguably a huge group of villages. It still feels that way, if you are only subscribed to sensibly small subreddits and you experience it through the prism of old.reddit and third-party apps like Apollo. Reddit doesn't think that that model is the future, though, and the mainstream Reddit experience has evolved away from that and toward the algorithmic feed model.
I would be wary in assuming that Discord's interface and community model will remain the same as it seeks ways to monetize.
Both seem to work and people are able to choose. I think it is also important that reddit facilitates a very different model of interaction, a discord server with a thousand users can be extremely active and engaging, while a subreddit with a thousand people tends to be quite "empty".
I think that this demand for continual growth is what destroys community. There's a word for unchecked growth: cancer.
However it has the "too easy to reuse an account" problem that has its own issues, too.