When "Dynamic SSH key injection" is enabled for RHEL9 VM, the ssh key is failed to be added to VM, the error is 
QEMU agent command 'guest-ssh-add-authorized-keys': failed to create directory '/home/cloud-user/.ssh': Permission denied'

4.15 and 4.16

100%

1. Configure the public ssh key via UI: Virtualization -> Overview -> settings -> User -> Manage SSH keys
2. Create RHEL9 VM from UI: Virtualization -> Catalog -> Templates -> RHEL9 template -> Customize -> Enable "Dynamic SSH key injection" under "Scripts" tab
3. Wait until the VM is up

1. AgentVersionNotSupported is showing in VM status, which is misleading
2. Check VMI events, could see the error
QEMU agent command 'guest-ssh-add-authorized-keys': failed to create directory '/home/cloud-user/.ssh': Permission denied'

SSH key is added to the VM