I think the only convincing reason given to lock this section is the concern about the off topic conversations. Even then, it seems overly rigid. A lot of the "off topic" material (discussions of rumors, for example) is still related to the character themselves, even if indirectly. They might change the circumstances or expectation that a certain character will be included or not. There's also a community aspect: It's different to discuss these things in neutral spaces versus with your fellow character supporters. I think the difference is one worthwhile in noting and preserving; I don't think it's a bad thing.
As for the character speculation not being the site's priority, it is what it is I suppose. It is a strange position to take, however, when a large part of the community is waiting for and has been discussing the topic for months. Stranger still when this discussion will take center stage soon enough. In that sense, the decision seems out of touch.
Of course, we are still getting a character thread. That's good. It's unfortunate, however, that now one has to log in to even view the new thread/subsection. That sounds like it will generally discourage visiting.
I know there are a lot of lurkers in this thread, too. If you haven't already, you should follow us @BringBackKRool on twitter. If you don't feel like joining, follow K. Rool news there.