Being a CM on a forum takes up hours of your time, every day. Even with a dedicated team to read and analyze posts you're likely to spend most of your work day just in the forum.
The return simply isn't high enough to justify that, not when there are more accessible venues like Twitter, Tumblr, Facebook, Instagram, reddit etc.
To make it worth their while they would have to be more active in the forum, they could poll us, they could ask for our feedback, they could answer questions and snuff out most of the volatile discussions by giving us real information. But that would require an investment and carries a risk... so why do it if they don't have to?
Especially since now the fans are spread out over several social media sites, you'd have to have a CM for each one and then put it all together at the end of the day.
That's a lot of work and I can see why they cut out out the most demanding part (the forum).
Many many years ago, so was I.
That would have been different.
You would have made a fine pair of mods. 
Consistent? She had barely over 400 posts. There were threads on these boards that got that IN A DAY.
The only thing more pathetic than that is Conal's 200-ish posts. Heck, his five posts in here represent over 2% of his entire BSN career. And he's a member of the Community team? BioMod01 has more posts just from stating they are closing threads.
Honestly, I didn't know she was the CM for a long time, I always thought she was just a cosplayer.
When I think of Community Managers, I think of people like Sanya Thomas (EA Mythic) or some of the CMs working for GOA. I know one of them (Sterntaler) joined EA Mythic, then was merged into BioWare and I think now he's working for Bethesda. Those people connected with the community, they were the ones who would get answers from the devs and who brought issues of the playerbase to the developers.
I have never seen anything like that here.