If the complain have some argumentation whatever how biased they can be, why not ?
I don' like NTR, but don't hate it either. Therefore some words about it in a review can change my mind, in a way or another. Obviously, the classical, "the fuck with all this NTR", will do nothing, but something more constructed can still be usefull. Take
Mike's Obsession, by example. One review can easily be something like, "it's full of NTR, the wife force you to let her fuck who she want, then just left you like the piece of shit you are". So, ok, there's none avoidable NTR, but it clearly seem to be part of the story's premise, not the main content of the game ; since I'm not a weak little boy, I can stand few NTR scenes and I'll give a try to this game.
It's was a pure complaint, but it still gave some usable information.
And the same can be said about other borderline fetishes. "What the fuck with all those piss scenes ? Each time you open the toilet's door it's to see a girls pissing" ; well, ok, anyone who don't like water sport, and is smarter than the guy who wrote this, will know to avoid the toilets. Once again, a finally useful pure complaint.
I implied it in my first comment, it depend of the person who read the review, as much as the person who wrote it.
The fact that the author of the review wasn't able to do some critical thinking while writing, doesn't mean that the person who'll read his review can't look at it in a more critical way.