Anger does not reduce your negatve emotions, it often increases them. Seneca did have ome good advice, i think so. One of his words of wisdom was to try to nip it in the bud. The idea that you would not want to deal with anger when you have fully lost it, but when you're just like a little irritated is good advice and consistent with modern scientific research on emotion regulation.
Also: why do we treat pets better than people?