A lot of fetishes are stupid. To name a popular one, harem is pretty stupid too. How can you believe multiple women are ok to share one guy. At best it's only temporary agreement but with the expectation to become his only bitch wife
That's the selfish harem type. I much more prefer the harem that has one person as the center but is very independent between itself. It works with or without that person being involved directly, like the harem in The Last Sovereign.
Also, harem is usually the fetish where you think of you as the person being served by so many woman/man/futa/'whatever the shit you want to serve you' and being the center of their complete attention and devotion, and yes I do dislike this type of harem A LOT. I'm not much for harem in any shape, I like freedom so I would be more for a poliamory type of relationship with multiple people, like they all like each other and want to fuck each other.
But I digress. What I actually meant with NTR being stupid is that it's over complicated as a fetish. Harem is simple, futa is simple, voyeur is simple, MILF is simple, Sadomaso is simple and even stuff like scat and watersports are simple.
NTR though... it needs so much stuff for it to works as fetish that it just make the whole thing stupid and pretty unworkable. If you take one of the many variables it turns into another fetish that is way more simple and approachable.
It's why I see so many of the NTR enthusiasts to be annoying, they can't see a girl talking to a guy that is not the MC that their brain immendiately goes "SLUT! THAT'S NTR!". I don't kinkshame people no matter what, but I can't help thinking "Really dude?"