If I understand correctly, I now must subscribe to Anthos ($$$) in order to run my Cloud Run containers in my own GKE cluster. Without Anthos, I can only use the fully-managed edition of Cloud Run. Or, presumably, I can set up self-managed Knative in my non-Anthos GKE cluster...
Product Manager for Cloud Run for Anthos here.
Yes, your understanding is correct, though I can't comment on the price point. Note that there's a free trial of Cloud Run for Anthos available until May 2020.