Uhm... KotOR2 was their creation, and moreso their coding than the forums. A lot moreso. Plus someone had to pay money in order for you to play KotOR2, which is why there is an expectation of quality. These forums are neither the focus of the company nor a requirement for them to maintain.
All that said, they do maintain the forums and keep them relatively bug free. The fact that it took anyone a year + to mention a bug that has been around since the forums were created illustrates just how trivial the bug is. I'm sure Obsidian will do something about it, at some point, but you have to keep your priorities in order, and these forums are bottom rung.