This applies to all the sub-forums, not just OT.
I pine for the days of 6000 registered members and forum sotware that wiped the database every once in a while. I pine slightly less for the days when there were maybe 20,000 members and a fresh new piece of forum software that didn't lose everything on a regular basis. Everything after that I don't so much pine for, as I do cringe about it.
Sheer number of users and posts are a major problem. It took half a decade to get to like 60,000 accounts, and then it doubled in half the time. It used to be possible to actually read every thread in every sub-forum (all 5 or 6 of them), and postcount was just a friendly rivalry. Now postcount is a goal.
Of course age is also an issue. I've gotten older, many of the people who were posting when the forums started are gone, larger numbers of younger people have joined (which only makes sense as older people are less likely to be getting online and discovering this type of forum). In real life, people my age are starting to look at young people and wonder what's wrong with them, how they can listen to that music, how they can be interested in things like texting each other on their tiny phones all the time. Same thing happens with online discussions.
It would have been nice if AT had aged along with those of us that were around in the early days, remaining a place with relevance for us, but it didn't. Some are still here though plugging along, but I think most of the really early people are gone. I'm just here because I can't go jump into some other forum and learn their ways and culture, when they're largely following the same demographic and types of users that AT has, for the same reasons.
Of course, I also blame some staff and types of behavior, but I won't go into it beyond that.