that DU was originally created as a "political" discussion site that supports the Democratic party and Democrats. But because people have so many other interests outside of "politics", there were smaller groups that were added over the years (by DU member requests) to satisfy that need to "take a break from politics" and engage in a "community" setting, alongside others who still follow politics as much as this membership does. I know there are some who I dub "Lounge Lizards" who I rarely or never see posting outside of the Lounge.
The current topics have been consolidated with the move to DU4 but back when those smaller groups were created, there were many members who were very active discussing those issues and they ended up cluttering and pushing out other discussions in General Discussion. At that point, there appeared to be a need to create a place for those discussions. But as time went on, many members of the-then active groups either passed away or moved on, and that is when decisions needed to be made about whether to combine groups or just deprecate them.
I think that EarlG made DU customizable to a good degree, to allow people to filter out stuff (forums, groups, and even subjects by keyword) that they are not interested in, and members can subscribe, not only to people, but to forums/groups.
I remember way back trying to decide whether to join here or Daily Kos. The DKos style was basically an OP and then what is a "comments section" below - e.g., like a "weblog" thing. I preferred the old BBS style formatting having gotten used to it on the old USENET back in the '90s, as well as some of my hobby forums. To me, it makes it easier to search for subjects and content. I suppose an alternate is how Reddit does their categorizing.
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