There is a difference between busy for no reason and busy because of information density. The busy examples in this article aren’t information dense. They just have a ton of different flower types, random animals, background characters, unrelated structures, many different colors and many different shades of those colors, etc. But the information they are trying to communicate is minimal.

A bus schedule or a parking sign is very information dense. It’s trying to communicate a lot in a limited space and as a result require getting used to.