Video game reviews are not politics. Just having the best argument doesn't mean what you're saying will actually hold true for most people.
You could make the most compelling argument for why the QTEs in Resident Evil 6 actually aided the immersion and made that game a masterpiece, and the people reading could totally buy into it. But once they actually play the game and 90% of them realise the argument was total BS, they're probably not gonna feel like the review did them justice.
And I already made the point that perfect objectivity can never be achieved, but it is their job to be as close as possible. There are universal truths that most lifelong gamers can agree to e.g. 30fps is obviously worse than 60fps(not accounting for resolution and genre etc.); yet some publications/developers have even tried to make arguments against that, and some 'gamers' even bought into it.
Objectivity is not a myth, and even though perfect objectivity can never be reached (cause we haven't all had the same experience and history in gaming), it should still be the job of a reviewer to try and get as close as possible.
I don't even mind if they add personal sides notes into their reviews, as long as they make sure it's known that's only their opinion, or whether they feel it actually has an objective affect on the quality of the game. I don't expect them to be perfect, but I expect them to try. It is their job to be knowledgable on the subject.
