Per the design doc [1], ClusterNode can be applied to private subnet only, if OPENSHIFT_INSTALL_AWS_PUBLIC_ONLY is not set, but installer did not report any error which creating manifests against following config: (subnet-04ed90d39b605e4f2 is a public subnet)

platform:
  aws:
    region: us-east-1
    vpc:
      subnets:
        - id: subnet-04ed90d39b605e4f2
          roles:
            - type: IngressControllerLB
            - type: ControlPlaneExternalLB
            - type: ClusterNode
        - id: subnet-07a9b2e507f3f769d
          roles:
            - type: BootstrapNode
            - type: ControlPlaneInternalLB


https://github.com/gcs278/enhancements/blob/30f44ee0cd57dc4ba3b72e10c0b8f1614970d0e0/enhancements/installer/aws-lb-subnet-selection.md?plain=1#L67
    

4.19.0-0.nightly-2025-04-04-170728
    

always
    

    1. unset OPENSHIFT_INSTALL_AWS_PUBLIC_ONLY
    2. assign  ClusterNode to a public subnet
    3. create manifests
    

created manifest successfully
    

1. ClusterNode can be assigned to a public subnet only if OPENSHIFT_INSTALL_AWS_PUBLIC_ONLY is set.