I'd have interpreted those as forums for players to discuss with other players, the description given by SE in each suggests just that. Given that there is not a specific forum for feedback you end up with the current situation where feedback is just thrown all over the place, the fact that you feel the need to make your post complaining about the state of this sub-forum is proof that this is very much the case.

People do not know which forum to post feedback regarding the game in; as such it makes sense to have such a forum as it then frees up clutter across both support forums and general discussion forums whilst also placing nearly all suggestions / feedback in a single sub-forum, this also makes ideas / suggestions more accessible to SE itself as they wouldn't have to trawl through every single forum to find threads titled "Suggestion: " to find the suggestions as is the case now. Of course I expect they keep an eye on all the forums anyway, but it does streamline their job a bit when looking for specifics.

Apparently I'm not the only one who thinks that it would be a good idea, as many other MMOs out there have specific forums dedicated to feedback/suggestions (in the case of WoW/Neverwinter I refer to the PTR/Neverwinterpreview discussion as that's where suggestions for future updates are left):