Helm is amazing. If you are migrating legacy applications that rely on filesystem config, you can publish that config in a helm chart that applications require as sub charts. Gives you the ability to do centralized, versioned config management for legacy workloads going to the cloud
Declarative paradigms get a bad rap but I really just believe its people who missing imperative/functional programmimg. Theres a reason the infra space has been using declarative syntax for years now