This isn't even slightly true. I use it as a verb a lot to indicate the introduction of a point, and when I use it as a noun I intend that the matter, while of interest (and therefore debatable and open to discussion), is of academic—or at least orthogonal and relatively insoluble—interest at that time. As an adjective, for example "a moot point", it means that the point is open to discussion, perhaps too much so, and in the context of saying it's "moot" you're saying that it's not appropriate to discuss.

Several different meanings, depending on verb/noun/adjective, but all of them suggest that the topic is eminently (perhaps too) debatable.