Perhaps due to the fact that OotS is a 3.5 comic, these have always been primarily 3.x boards. A lot of very vocal people in the 3.5 community felt betrayed when 4e came out, and their hostile behavior likely prevented a lot of would-be 4e newcomers from sticking around, thus preventing a large group of 4e players from forming. As such, we've always been a fairly small corner of the giantitp community.

It has been slow lately, but not unprecedentedly so.