I agree with your overall point, but I think people keep using BDSM as an excuse when that's not what this is. BDSM is built on consent, boundaries, and mutual agreement. Rape is the exact opposite because one person does not consent and is being coerced or forced.
That's why so many readers push back when people lump everything together under BDSM or dark romance when it's not . Having dominance themes doesn't automatically make something BDSM or dark romance. If a relationship starts with captivity, coercion, and rape, people are going to talk about that no matter what genre label gets attached to it later.

Since we're on the same platform, it's obvious people are going to criticize things that deserve criticism. Not every story deserves a happy ending, and if that idea bothers you, then there are probably still a lot of stories and perspectives you haven't explored.I like BDSM, and yes, this manhwa falls into that category. But are we seriously forgetting that it also contains r4p3? Their entire romance literally starts with r4p3, yet some of you expect people to stay quiet about it. Sorry, but slapping a romance label on a relationship doesn't magically erase how it began. If people can praise it, others can criticize it too.