The antonyms for the phrase "striking as being" can be many, depending on the context, but some common ones are subtle, unremarkable, ordinary, mediocre, and dull. When we use the phrase "striking as being" we usually refer to something that captures our attention, impresses us or stands out in a particular way. However, in some situations, we may describe something as the opposite of striking or eye-catching. For example, we can say that a person's outfit is subtle or unremarkable if it doesn't draw much attention. Similarly, a building or a piece of art may seem dull or mediocre if it is not particularly impressive or memorable.