When I joined Volconvo in April 2004 (within days of the join dates for many people here --- a very strange thing) the place was a hive of activity. It had its ups and downs, like WordForge. Somehow in the past year it went into a death spiral that still has me puzzled. But there's a warning there for all boards like this one. It takes commitment. Otherwise you show up one fine day and it's all gone.
Basically, this. I don't think message boards will die away entirely. Not everyone wants to share every thought about everything on a venue where all of one's friends and family post at as well. That's why 4chan continues to be the dark hive of scum and villainy online that is one step above the Dark Web.