Scientific evidence, and in every possibly way you could define success.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3498890/
>This article investigates how personality and cognitive ability relate to measures of objective success (income and wealth) and subjective success (life satisfaction, positive affect, and lack of negative affect) in a representative sample of 9,646 American adults. In cross-sectional analyses controlling for demographic covariates, cognitive ability, and other Big Five traits, conscientiousness demonstrated beneficial associations of small-to-medium magnitude with all success outcomes.
This is only one example, these results are replicated in many, many other studies.
>Society and civilization are built around discipline and order, but it doesn't mean you require those qualities to have success.
Conforming to societies expectations really has nothing to do with this. No matter what it is you want to achieve in life, and no matter how passionate you might be about it, any worthwhile archievement in life requires discipline. Relationships, art, sports, philosophy, career... Achievement in any of those areas requires discipline.
Even if society was in a total state of disorder, you’d still need discipline to get what you want from life.