Many, probably most, kali-linux questions on this site are extremely low quality. They show no effort, lack any useful detail, are often extremely basic, frequently trying to do things the distribution is unsuitable for, and from users who have no interest in learning or aiding others to help them learn, or some combination of those traits. That is the answer to your title question: negative associations from a number of low-quality questions from often-belligerent querents.
That has led to a general distaste for questions about it that taints even the fair questions from users who mention that they are using it. Those questions get lumped into the same bucket as soon as the tag or a hint of the distribution appears.
Your question was not a duplicate of the supposed duplicate target, and nor are almost all of the other questions closed as a duplicate of it. That question is wilfully, cartoonishly, and insultingly caricatured. It is, frankly, not a positive element of the site at this point, let alone as something to tell someone is the same as what they asked.
Closing questions as a duplicate of that question is abusive. Voting to close as a duplicate like that is just a way of saying something that wouldn't be allowed in a comment1, mediated by the system.
The questions are virtually never "why is it hard", they are "how do I X?". The questions might be unclear, they might be too broad, and they're often legitimate duplicates of on-topic questions with actual answers, but they're not duplicates of that. Votes that suggest otherwise are not good-faith acts2. At best, it's a helpful see-also, and not a duplicate; at worst, it's just people getting off on the superiority they feel from belittling people they think are beneath them. Kali questions ought to be edited, voted upon, closed, and reopened in the same manner as other questions are (which is still likely going to result in most, but not all, of them being legitimately downvoted and closed on current form).
Generally questions closed in this way don't get reopened and the users disappear. For many of the questions, that was probably always going to be the case. On the other hand, it is also hardly strange that upon receiving that sort of welcome the asker doesn't go on to edit their question to add details such that it ends up in the reopen queue. They are driven off and the site preserves its reputation as hostile, elitist, and unwelcoming.
Kali questions and question from people using Kali are in general on-topic here, though in many ways it would be preferable that they were categorically off-topic to the current situation. Regardless, each question ought to be addressed on its own merits.
It is likely that for many of the questions that are both about appropriate uses of Kali and from users who have made reasonable effort, this community doesn't have the most suitable expertise. For example, questions about using wireless hardware in non-standard ways using Linux tools are on-topic, but not something that general sysadmins and users are likely to have experience with. Those questions may languish regardless. It's not always clear which questions are in which camp and it's not unreasonable for someone to ask.
I think the "Why is Kali Linux so hard?" question is a problem in itself. Another formulation of it might be able to convey useful information, but as-is it is just an attractive nuisance and I don't think that's repairable. It certainly shouldn't be put forth as duplicate to other questions, and even less so to yours that already had an answer.
1I will bowdlerise that comment as "go away, unintelligent person"
2Users who have reached the close-vote threshold, let alone realms far beyond, are well aware that the new question does not duplicate the old and does not have the same answer, and so we know that they are not suggesting in good faith that it does. We could believe that they merely thought it would be useful related reading and used the close-vote mechanism as a way to convey the link, but as that is not the role of a close vote the action was not offered in good faith. They could have a range of motivations within that.