That forum I signed up for in 2012? I don’t remember the name.
That Facebook group I joined in 2012? I still see the occasional post in the feed.
Also it’s vastly easier to find these communities in the first place. There’s no way to look for forums about a specific topic, if that exists at all.
Forum platforms could offer the same feature by interoperating with the Fediverse. You can sign up on one server and use that one identity to post content elsewhere. (Plus it also addresses the issue of needing a mobile native UX, there's plenty of apps that can interact with the Fediverse.)
You can just say "I also have these headphones and love them" and that adds value to the whole thing.
Maybe its just a factor of being small like you said.
In reddit/hn/twitter one feels ignored most of the time - no upvotes and feel like no one has read what you typed. Why did you even type it?
(I know this is the issue with forums that reddit-style sites fix...)
It's part of the relentless push toward greater resource allocation efficiency. Just as it is orders of magnitude more efficient to distribute perishable goods through a centralized corporate supermarket chain rather than a patchwork of independent corner markets, Reddit reduces the total amount of operations overhead that once went in to maintaining thousands of independent vBulletin / phpBB / Discourse instances in the aggregate.
With all the recent talk about supply chain resilience and the inherent trade-offs necessary to improve it, one might wonder whether such considerations might be weighed differently going forward.