Troll Kingdom was founded by disgruntled TrekBBSers who had either been permabanned or had had enough of the perceived censorship of fringe individuals / behaviors.
In the halcyon days, it was fairly active with some regular TrekBBSers - including some mods - crossing the line and participating.
Troll Kingdom peaked around the mid 2000s. As the wild west days of TrekBBS waned, interest in TK started to dry up. Other boards popped up in this tumultuous period, with WordForge being the most prominent (populated by similarly disgruntled TrekBBSers, irked by over modding).
The key difference between WF and TK is that WF branded itself on more than "fuck other boards" and is still fairly active. TK, on the other hand, continued to decline, with the majority of "talent" moving on to greener pastures. Eventually, TK was held up by only a handful of faithful (as far as any meaningful content goes). Unfortunately, the rest devolved to pure spam and empty attention whoring to the scant few remaining.
True TK / Pure TK was as a supporting character in the TrekBBS soap operas of the early-mid 2000s. Those days are a lifetime ago.
It is fascinating that it still exists, as anyone who contributes meaningfully undoubtedly has other outlets in which to do so. Sentiment would seem to be the obvious answer.
For additional insights into the early days, see
here