Of course, but those were not yet available in 2017. Skaffold v0.1.0 was released in february 2018, v1.0 (first version number which we would've seriously considered) not until november 2019. ArgoCD v1.0 was released in may 2019.

When we were first releasing this Helm charts were considered pretty unproven and AWS didn't have a managed k8s offering yet. It was very early days.