Forums were best before up/downvoting/likes/reactions and before sort-by-most-popular became a thing. When they were simply a discussion in historical order (possibly threaded) by topic. HN is halfway down the engagement slope with its voting mechanism, its inability to track which comments you already read, and its locking of discussions after a day or two. The last two points prevent long-form asynchronous discussions. The first prevents a shared and stable discussion order, and diverts attention capacity to giving/receiving up/downvotes and to one’s karma level.