Take a look at Kubeflow.org for an example. There are several reasons that a tool like that targets Kubernetes and not native AWS. One of the benefits of k8s is how portable and non-vendor-specific it is. Basically, it's become a standard platform that you can target complex applications to, without become tied to particular vendors, and with the ability to easily deploy in many different environments.
To be clear, I'm not claiming you can't do these things on native AWS, but rather there are wide choice of high-quality projects ready to go that target k8s.
- Countless Helm charts
- Development tools like Telepresence
- Many GUIs / terminal UIs
- CI/CD tools like Argo
- Logging and monitoring tools
- Chaos engineering tools
- Security and compliance tools
- Service meshes / request tracing
- Operators for self-healing services
- Resource provisioning
- etc...
