Can I use ingress-nginx as a reverse proxy?

Questions at the Kubernetes slack are always interesting and sometimes nerd sniping. One such question came along the #ingress-nginx-users channel where a user was trying to make the nginx controller work as a reverse proxy too for a site outside of the Kubernetes cluster in question. The user tried to do this with configuration snippets, without using any ingress object at all. However the ingress-nginx maintainers discourage configuration snippets, as they are scheduled to be deprecated.

Now normally to solve this problem, one would deploy an nginx and configure it as a reverse proxy, create a service and link it with an Ingress object to do this. Assuming you run Docker Desktop Kubernetes and you want to reverse proxy api.chucknorris.io, a solution to that would look like this. So nothing really fancy, just typical stuff.

Is it possible though that one can achieve this, through clever use of annotations, without any deployments? I thought that I could do this with an ExternalName service. Defining such a service is not enough, because the ingress-nginx works with Endpoints and not Service objects under the hood. And Endpoints are not created automatically for an ExternalName. Enter EndpointSlices and you can define the endpoints on your own. You can do so even with an address type of FQDN (beware though that this seems to be heading for deprecation, but for now it works). And you end up with a solution that looks like this:

# Assuming Docker Desktop Kubernetes, this is a reverse proxy 
# leveraging the ingress-nginx to reverse proxy with api.chucknorris.io:
# curl -k -v -H "Host: chucknorris.local" https://kubernetes.docker.internal/jokes/random
---
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
  name: chucknorris
spec:
  selfSigned: {}
---
apiVersion: v1
kind: Service
metadata:
  name: chucknorris
spec:
  type: ExternalName
  externalName: api.chucknorris.io
---
apiVersion: discovery.k8s.io/v1
kind: EndpointSlice
metadata:
  name: chucknorris-1
  labels:
    kubernetes.io/service-name: chucknorris
addressType: FQDN
ports:
- protocol: TCP
  port: 443
endpoints:
- addresses:
  - "api.chucknorris.io"
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  annotations:
    cert-manager.io/cluster-issuer: "chucknorris"
    nginx.ingress.kubernetes.io/proxy-ssl-verify: "true"
    nginx.ingress.kubernetes.io/proxy-ssl-verify-depth: "2"
    nginx.ingress.kubernetes.io/backend-protocol: "HTTPS"
    nginx.ingress.kubernetes.io/proxy-ssl-server-name: "on"
    nginx.ingress.kubernetes.io/proxy-ssl-name: api.chucknorris.io
    nginx.ingress.kubernetes.io/upstream-vhost: api.chucknorris.io
    nginx.ingress.kubernetes.io/proxy-ssl-secret: default/chucknorris-local
  name: chucknorris
spec:
  ingressClassName: nginx
  tls:
  - hosts:
    - chucknorris.local
    secretName: chucknorris-local
  rules:
  - host: chucknorris.local
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: chucknorris
            port:
              number: 443