Microk8s getting started tutorial: how is accessing cluster IP actual work?

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Hi all!
I’ve been trying microk8s and the getting started tutorial on the homepage actually does something I would not expect to work (and it does not, when I repro it)

So on the website: https://microk8s.io/ there is a shell recording of the following commands after having an nginx running:

$ microk8s kubectl expose deployment nginx --port 80 --target-port 80 --selector app=nginx --type ClusterIP --name nginx
$ microk8s kubectl get all                         ip-172-31-40-63: Mon Sep 28 11:50:20 2020
NAME                         READY   STATUS    RESTARTS   AGE
pod/nginx-6799fc88d8-9gnkw   1/1     Running   0          53s

NAME                 TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)   AGE
service/kubernetes   ClusterIP   10.152.183.1   <none>        443/TCP   2m44s
service/nginx        ClusterIP   10.152.183.7   <none>        80/TCP    12s 

NAME                    READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/nginx   1/1     1            1           53s

NAME                               DESIRED   CURRENT   READY   AGE
replicaset.apps/nginx-6799fc88d8   1         1         1       53s

Ok, this bit exposes port 80 to port 80 and then the example does the following on his ubuntu host machine:

ubuntu@ip-172-31-40-63:~$ curl 10.152.183.7
<!DOCTYPE html>
<html>        
<head>                                                                                             
   <title>Welcome to nginx!</title>                                                        
              <style>                                                                                      
             body {                                                                                            
        width: 35em;                                                                                         
 margin: 0 auto;                                                                                       
font-family: Tahoma, Verdana, Arial, sans-serif;                                                 
 }                                                                                                
 </style>                                                                                             
 </head>                                                                                               <body>                                                                                                <h1>Welcome to nginx!</h1>

When I try this, I cannot access the IP at all (I know mine has a different assigned ip), but it would also be awful, if I could, wouldn’t it?

Why is the example working at all? The exposed port is of ClusterIP type and not a nodeport.
AFAIK this would be possible at best when the example previously spawned a container like busybox and entered its shell to do curl from inside the cluster. (Which is not visible in the getting started thing).

But for a newbie this curl step is super magic as it skips the “understand the whole k8s thing first” and produces results that me as a beginner won’t get.

I am probably missing some important thing and would love to get a hint about what I am getting wrong.

Thanks!