Calm is a competitive advantage nobody can easily see.

Nobody sees composure. It produces no visible action, and its results appear as decisions that turned out well and mistakes that never happened, neither of which get attributed to anything. Meanwhile it is doing an enormous amount of work, letting you think clearly when others cannot, which over a career adds up to a real difference.

Treat calm as something to train rather than a temperament you either have or do not. Deliberately put yourself in moderately stressful situations and practise staying settled. The advantage accumulates quietly and it is genuinely difficult for others to copy.