When I asked the reviewer who originally posted the duplicate link why he was duping this question, he referred me to this Meta post: What should we do about Kali Linux questions?. In the top-upvoted answer it says "I do not propose systematically closing Kali questions!". Although the question has an accepted answer, it was marked as a duplicate of a question that is not specific to the question that was asked, and then it was (incorrectly??) closed.
No, I agree that one shouldn't have been closed. This is a surprising change since
apt-get has been the standard for many years and even experienced users might have been blindsided by it.
I had completely misunderstood the situation. I thought that Debian and, by extension Kali, no longer used
apt-get and only shipped with
apt. I thought this was a new change and, therefore, would indeed surprise many users. As was explained to me in chat that's nonsense,
apt-get is part of the
apt package and the only way to have one without the other is via some sort of PEBKAC.
Nevertheless, while I can understand closing that question as non-reproducible or too broad or unclear (as some of the close voters had indeed chosen to do), I don't think that one was a valid duplicate of the broad "Kali is not for newbs" question since it was a specific problem and actually answerable.
So, I have reopened the question and would like to take this opportunity to ask the community not to automatically close in favor of the "Kali is hard" question. We should only use that as a dupe target when the issue is obviously that the OP is new to Linux and really shouldn't be using Kali because they are new to Linux.