Managed container services (like Amazon ECS) are a sweet spot for me across complexity, cost, and performance. Mid size companies gain much of the modern development workflow (reproducibility, infrastructure as cattle, managed cloud, etc.) using one of these services without the need to go full blown Kubernetes.

It's lower level than functions as a service, but much cheaper, more performant, matches local developer setups more closely (allowing for local development vs. trying to debug AWS Lambda or Cloudflare FaaS using an approximation of how the platform would work).