alt Hacker NewsSalon used to have a terrific forum, with some of the most brilliant contributors I've seen on the web in their "International Issues" section.
One day without warning, they deleted it.
Complete contempt for writers who were frankly far superior to any on staff. I was just a lurker, I've no personal investment beyond that.
I can't remember the last time since that that I visited the site with intent; the arrogant, contemptuous destruction of brilliant writing - that's Salon's legacy for me.
The amount of early 2000's forums I can tell a similar story about is incredible ... companies willingly just jettisoning their audience.
It's either killing off forums completely, or "upgrading" to the point of being unrecognisable, or requiring everyone to make a new account and ... I can't even be bothered to write it.