Anecdotally, for the amount of problems I have seen them solve in short order. Yes. They force an idea in the mind to become concrete and logically digestible to other members of the party. If you can't draw it in a manner that other people understand, you don't understand the idea well enough yourself. It is also free flowing. Ideas can be added to and removed quickly with an interface that almost all humans have been taught to use since a young age. It only contains 3 parts. The pen, the board, and the eraser. No software with far too many options to understand. No weird bugs that crash in the middle of a presentation. Pictographs can transcend language barriers. Software sellers will never create such a simple product, there is little value added reason to.
So yea, if not magical, far better than its competition in portraying ideas.