istio: IstioOperator spec.meshConfig is not applied

Bug description IstioOperator spec.meshConfig is not applied.

Expected behavior

When I apply the IstioOperator CRD like this

apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
metadata:
  namespace: istio-system
  name: istio
spec:
  namespace: istio-system
  profile: default
  meshConfig:
    outboundTrafficPolicy:
      mode: REGISTRY_ONLY

The generated config map should have synchronized meshConfig

Steps to reproduce the bug

1. Run istioctl manfiest generate -f operator.yaml with the above manifest
2. See that the output config map still has outboundTrafficPolicy.mode set to ALWAYS_ALLOW

Version (include the output of istioctl version --remote and kubectl version and helm version if you used Helm)

How was Istio installed? Using the istioctl

Environment where bug was observed (cloud vendor, OS, etc) Cloud vendor: AWS (EKS) OS: AWS Container Optimized EC2 Linux