Genetic engineering has been an interesting, because relevant, SF theme since Brave New World.
However, this has nothing to do with the newest Abrams' blockbuster. That Khan is not a madman, nor is he a terrorist. He's merely an operative for an admiral trying to instigate a war. Since the issues of war and peace are not actually dramatized, that's not relevant either. I admit that Kirk coming out against war is nicer than the Kirk who kills people about to die for the fun of it, but this is not particularly relevant.
In fact, since preventive war has been pronounced policy, the movie pretty much dodges any possible relevance. It's just the adventures of Space Cocksman and Stick-Up-His-Ass. Apparently lot's of people have been watching Star Trek that way all along. Apparently I've been overrating the show for years now.
As for the notion that it's all subjective? The question then is why people who think that post anything. All they need is a letter grade or some number of stars.
I don't think we can honestly say that you can't be objective (not perfectly objective, that's a nonsense standard designed to forestall criticism.) You can say something meaningful about plot logic, rationality (or lack of) character motivation, the quality of music, the originality in us of 3D, an actor's skill in performance, etc. in a way that we really must concede to be objective.
But these individual elements are not transitive. We cannot neatly order these aspects in such a way as to weight the relative contributions, then sum to a more or less objective amount of artistic goodness. For example, it is an objective fact that much of the last movie was devoted to staging variations on high points in The Wrath of Khan. As such, it is incontestably derivative. What cannot be objectively rated is how much this adds or detracts from the effect of the movie.