Or anyone else who is part of a niche community I guess. One popular example is xda-developers.com - even in 2023, it’s forums remain relatively popular, and there’s no real replacement for it. Reddit had several Android-related subs, but they don’t see the kind of discussions that XDA sees.
One big difference is that traditional forums are more suited for long-term and lengthy discussions. Reddit, Lemmy and similar sites primarily revolve around the “now” - posting or discussing the latest news and trends. Once a post falls off the front page, no one cares about it any more - whereas on a forum, a single thread can have a lifetime of many years.
Also, the fact that there is no points/karma system means every comment and post gets equal visibility, and there’s less chances of an echo-chamber forming / ass-kissing / meme / low-effort posting. Like look at SchnoodleDoodleDoo on Reddit - every single comment of their’s is a lame poem that adds no value and wastes screen space - basically spam - yet every time they post, they get a flood of replies from people like “Schnoodle you’re the GOAT, marry me xoxo” etc. Honestly, it gets very annoying seeing such ass-kissing and useless comments on every single thread.
And same with posts - because there’s no points system in a traditional forum, you get equal visibility over every post. Whereas on sites like Reddit, you’d have to pray that your post gets enough upvotes so that people will see it (or alternatively, buy upvotes), AND you’d have to also make sure you post at the right time so they people will see it, otherwise your post will quickly dissappear from the page. Lemmy, since it’s till fairly niche, doesn’t have that issue right now, but once it’s popularity grows, it’ll suffer from the same issues associated with votes and timing. Which is not very ideal for someone posting a question wanting help with something.