For individuals, though, might competitiveness often be driven by insecurity, and the point stands?

Point is that competition is fueled by insecurity. If you are happy, truly content, with yourself you will find competing extraordinarily tiresome and unnecessary. Not saying it’s good for society by the way. I think our civilization needs the pathologically insecure to be disruptive and create room for innovation. Related traits are narcissism and psychopathy. Painful, but useful, in small doses.

Musk, Altman, Bezos they are basically caricatures.