Either paramount or meaningless, I suppose. Culture, in my estimation, is a fundamentally social concept; "individual culture" is meaningless. However, if you're using the term to refer to "taste" or "personality" or "individual perceptive and analytical framework" or some similar concept, it's arguably the most important and foundational undertaking for any individual.

Especially in the modern world, where an individual is presented more conflicting perspectives than they can possibly (practically or logically) accept simultaneously, we are forced to select and curate our own perspective and taste.

In short, the world is too big and contradictory for us to externalize our perspective. We have to choose a path, if only out of necessity.