Eh, it is less about that and more about KYM's upper administration refusing to handle NSFW content the way every single other website with content aggregation features has done so far: simply give it a dedicated space and filters.
Tumblr..? Allows it fully, tagged and filtered. Twitter..? Allows it fully, tagged and filtered. 4chan..? Allows it fully, tagged and filtered, and even makes dedicated boards for it. Reddit..? Allows it fully, tagged and filtered, and has dedicated subreddits for it. Less known sites like FunnyJunk and all Booru sites..? Allows it fully, tagged and filtered. DeviantArt..? Allows most of it, tagged and filtered (poorly, but still). Facebook is probably the oddest ball of the bunch, though they still have more lenient rules about it than KYM, and that is the most public site of all mentioned here and probably the most public in the entire world (which also owns all submitted content as soon as it is uploaded there), so go figure. They would rather have nipples than political commentary, I guess.
None of these sites are primarily used for NSFW stuff (well, maybe Booru sites are), and yet, that did not stop any of them from applying those measures and allowing it. All because this site is, as has been stated before, "not a community-dependent content aggregation site like those, but a documentation site more akin to Wikipedia", which is not only a contradiction (Wikipedia IS community-dependent by all accounts, just not a small community of known faces. They do not even depend on ad revenue to keep it up and running, and 99% of their articles are user-made – no such thing as a Staff frontpaging stuff there), but also – let us be honest with ourselves here – mostly wishful thinking more than anything. Just look at the Trending galleries: their entries were all created by non-Staff members, or at least their parent entries were, and those bring in more cumulative views than all non-viral frontpaged Staff-made entries, and of note, some of them because of NSFW content, not in spite of it, and they are all based on community preferences, not what Staff or mods do or say. For all intends and purposes, KYM's content and views function much closer to content aggregation sites than to wiki-like sites. We just want to be the Wikipedia of memes, but that is simply not the case. It just has entries roughly resembling that format. KYM is heavily understaffed for such an ambitious goal, for starters.
Hell, what is more, I can actually prove this mathematically legally:
"Literally media manages a collection of highly successful humor and entertainment websites to create one of the world's largest content platforms for the Millennial and Generation Z audiences.
Our portfolio of legendary digital brands include eBaum's World, Cheezburger and Know Your Meme with a combined audience base of more than 24MM monthly unique users."
From Literally Media's main site, KYM's owners. Does it sound like they view or treat KYM like a "wiki" site..? Does any of that sound like a description they would give to what they believe to be primarily a "documentation" website..? Can you use any of the words I bolded out to describe Wikipedia's purpose and function..? I rest my case.
With that said, entries that DO go viral, like Ligma and Momo, usually bring over 1 million views, which is more than what the trending images bring, so there is a separate argument to be made in regards to just how important Trending images are in the big scope of things (and the whole NSFW debacle, by extension), but that is another story for another day.
Consider all of the above and we have today's current situation. Going in circles and big, ultimately pointless loops of word semantics between mods and users about the "relevancy and morality" of NSFW content that serves nobody but the speaker of such things, and the same old, tired arguments about "why was my image removed, it was totally inside the rules" popping every month or so which never amounts to anything but a mechanized response, and the inevitability of it happening again. You think any of the sites I mentioned ever wasted any time on such things..? Hell, half of them had NSFW filters and spaces from the start. And again, I cannot stress this enough: none of them were actually made specifically for NSFW stuff, just like KYM. That did not stop them. And perhaps of no small importance: they still have decent ads on them, with no sponsors breathing down their necks. Even 4chan, for Christ's sake. Hell, I am pretty sure even Shadman has better ads than KYM, and that really is a comical event in and on itself.
So, I disagree with the common user notion about the "morality" of NSFW content being a factor because, if anything, there is more acceptance than stigmatization towards it despite everything said and done, and I ALSO disagree with the mod notion about the "relevancy" of NSFW content being a problem because by that logic, plain text posts not related to any meme and non-lewd fanart are just as relevant as NSFW and nobody bats an eye about those, and I also see no sponsors starting fires at KYM's HQ when a lewd artist/character gets literally frontpaged of all things. I stick with the more globally accepted internet notion of, plain and simple, avoiding unnecessary headaches and squabbles and just make dedicated spaces for all types of content that require so, and be done with it all. Whoever likes it likes it and whoever does not just avoids it. Period. Some sites even do it for political content; I am rather impressed it has not come to that for KYM, but it is clearly overdue for NSFW content.
But eh, guess this is all also just wishful thinking on my end and this cycle of morality/relevancy arguments about it will never end and nothing of actual productivity will ever be done about it, all while KYM's sponsors still find a way to fuck the site over other overlooked things, thus making all of this a moot argument, anyway. Might as well put more hope into getting editable comments; that is actually a more realistic possibility, believe it or not.