Talking very loud and very fast does not make what you say substantive or useful. Content is what really matters. Agree/dis/why?

Many  promoters on TV talk loud and fast and interrupt and talk over people. That is not how you convince people of the value of the noises you make. But maybe that really does work with some audiences and that's why they keep doing it. Does it work with you? Loud fast non-stop? Why?