Actor model (Akka/Orleans) for high-concurrency systems: still relevant?

we're evaluating options for stateful, high-concurrency services, and the actor model, specifically something like akka or orleans, keeps coming up. the promise of isolated state, message passing, and built-in distribution appeals for certain parts of our system, like real-time bidding or complex game states. however, with the rise of stateless containers, kubernetes, and serverless functions, the operational overhead of managing actor clusters and ensuring state persistence and recovery feels a bit old-school. are people still successfully deploying and operating actor model frameworks for new projects that require distributed state? what are the practical challenges and benefits compared to more modern, cloud-native approaches that might use redis for state or k8s for orchestration?