It depends on majority classes are more important or minority classes are more important. For example the classes are not balanced in this data: https://towardsdatascience.com/multi-class-text-classification-with-scikit-learn-12f1e60e0a9f but I think it is ok, because we care about the majority classes the most. In other case, we may care about minority classes, then we might have to balance it
Changing the world, one post at a time. Sr Data Scientist, Toronto Canada. https://www.linkedin.com/in/susanli/