I noticed that the meta "How to Ask" box says:
We prefer questions that can be answered, not just discussed.
I think this might be a bug due to the fact that one of the uses of meta is for disscusion, but it does say prefer so I'm not quite sure.
I think the important modifier in that sentence is "just". I don't think it's implying that there should not be any discussion on Meta, but that a Meta question should be more than just throwing a topic out there and letting people have at it.
For example: "What do you guys think about downvotes?" is only a discussion, as it doesn't have any sort of answer whatsoever, but "Are downvotes potentially being used improperly on the 4th day of the month?" still allows users to discuss the matter without it being completely freeform, while having definitive answer(s) ("Yes, my evidence is..." or "No, but, I have noticed..."). While discussion is more actively discouraged on SO and the other sites on SE, Meta at least needs to have a modicum of discussion to keep her wheels turning.
So, while I think you make a decent point, there's a bit of nuance in that "How to Ask" statement, and I think the choice of words was deliberate.