I cannot possibly over-exaggerate how bad Facebook is as a topical forum. It tries to help, by reordering topics in the order it thinks you might want them to be. It sucks at this, because it is a dumb machine-learnt (durr) tool optimized for engagement, not usefulness, and it shows. It shows _so hard_. Any programmer could knock off a better topical forum in a weekend. Facebook should be embarrassed with how bad this is. PhpBB ate their lunch ten years ago.