Doesn't that require Istio and a few other things as well? I wouldn't wish Istio configuration and maintenance on anyone but the larger shops/teams. You might not be technically locked in, but not everyone can afford to dedicate the attention to tuning and maintaining Istio.
Source: at mid-sized company who has Istio in the stack.
Cloud Run implements the Knative API, so you can actually take it away and run it on any Kubernetes cluster anywhere on a cloud or in your datacenter.