the reason is simple, people just wanted to bully vulnerable users, say edgy shit and slur and sir didn't want to deal with it anymore.
I enjoyed all of those things and am mildly disappointed, but I'll just go back to not posting on the forums.
That was the most active board because people felt free to say whatever they wanted without getting infracted or banned, now that there is no such place the forums will be a much quieter place.