As one of the few people who does interact with a certain number of threads, mostly ones that relate to my various hobbies- I'm not sure how to answer. The threads are there, it's just that very few people interact with them.
This often happens when a discord exists. But to be fair, the site was dead before we had that. if anything, the discord helped bring back some missed members and finally expelled easily one of the most obnoxious members we knew. The one that made even me look good by compare!
I think Forums are just a dying breed. If you think this forum is dead, you should see the barren spectacle of cadavers thats is the rpgmakercentral forum. Even RpgmakerWebs size is rapidly decreasing as people flock to discords. As I discovered, there's no better way to kill a sights prosperity than to make a discord for it. This applies to forums that are prospering, ours hasn't since 2009. So far us, a Discord server ended up being more to our benefit than not.
There's also the fact that a lot of the people who use to be actives have much less time for the site than they use to. I recall NathanielW and Xileflan were regulars once upon a time. Even Coyote has become more busy as his obligations stack up.
Nathaniel finished his game so he'll probs be busy on the next big project for a while. Xileflan works on Minecraft now, among all the regulars past, I'm the only one who has more or less fully escaped responsibility. I just make games, I never really stop. Even in times such as these, I'm thinking about games to make every minute I'm awake and asleep!
Oh, speaking of "these such times"! Do remember this is the time of year where a lot of people are hanging with their families and all that funny nonsense mortals tend to do! I myself am taking a break, after the hectic workload I took three months to get through most of, I kinda need it.
Welp, there's my two cents, lengthy as it is! Not sure it'll help but it's all I feel I can really answer with!