Why is the SDMB membership declining, and what's the best way to add younger members?

I will say I had never opened the Trolls R Us thread until it was mentioned as a low point here yesterday, and when I see posts like this:

I frankly just don’t understand what value that thread, or threads like it, and the sort of posts it generates, are adding to the forum. To be frank I’m not even sure that r/The_Donald, before reddit shut it down, would allow such invective and deranged ranting targeting individual posters. That just isn’t a healthy sign for a community. If I had never been on these boards before and stumbled into a thread like that, I’d surely not have ever registered here, like that’s as bad as stuff found on 4Chan or etc. It also just literally advances nothing positive at all for the SDMB.

I think a lot of the interminable pit threads that are thousands of posts of people just spewing hate filled rants about one thing or another are not only bad for the board, I think they’re likely not great psychologically for the people participating in them. I don’t think participation in community like that is a healthy or good thing, and having seen the bile in some of them for the first time I frankly feel a lot more strongly that the pit needs seriously reformed or removed.