Node 2 and 3 configuration file missing authorization: enabled in Lecture Notes

MongoDB University M103: Basic Cluster Administration
#1

Hi,
I noticed that the line in the configuration file for node 2 and 3 in the lecture notes are missing the security line:
authorization: enabled

which is shown in the video.

#2

This line is implied when you use “keyfile”.

#3

Thanks for the clarification. Why was that line added in the video if not needed?

#4

He says in the video (1min10) that the line is implied but he leaves it “for clarity”.

#5