To run k8s on bare metal server clusters there's only Metallb option to bring user traffic into clusters NodePort services, via externally exposed IP address(es). I wasn't talking about k8s internal load balancers and reverse proxies

This is not true at all, you can use a self-provisioned edge (load balancer) like haproxy.

See https://kubernetes.github.io/ingress-nginx/deploy/baremetal/

You were talking about cloud, now you are talking about bare metal?

Of course you have to route traffic to your cluster, but you are implying some cloud based load balancer lockin which just isn't true

I believe the OP is talking about LoadBalancer (https://kubernetes.io/docs/tasks/access-application-cluster/...), and I believe you're talking about Ingress (https://kubernetes.io/docs/concepts/services-networking/ingr...).

It's very commonly used by the ingress controllers. You can get things working with hostNetwork or custom service port ranges, but that's a lot rarer than doing it via load balancer.

Third option would be to expose pods directly in the network. EKS does this by default, but from my experience it's quite rare for people to leverage it.

Yes, an ingress resource will typically create a load balancer if you are in the cloud, but not a service resource.