Well, I somewhat agree, although the creator of the original Lord of the Rings series took care of that problem by making the vast majority of the followers of Sauron, except Saruman, Orc like creatures, and you could barely see the others.
Also, I doubt the people of Rohan were supposed to be Germanic. Although there is some debate about it, Tolkien was, imo, reacting to the two World Wars he had witnessed (as well as the despoliation of the natural world by industrialization). He wouldn't have seen Germans as the "good guys".
If anything, I think the people of Rohan were based on tales of the Indo-Europeans of the steppe.
The "heroes" were the people of the West, ie. Western Europe.
I'm not, for what it's worth one of the Tolkien fanatics who want every detail of the books transferred to film. However, I am indeed very, very attached to them, and have been since I read them in high school.
We can't re-write the whole Western canon so newcomers or minorities can "see" themselves in these representations. There are plenty of films set in more modern times which can provide that opportunity.
That said, in this particular version of Tolkien's work I'm less bothered by it because of the excellence of the acting of the main elf character, especially in contrast to the terrible acting of the woman playing Galadriel.
I wonder, given all this effort to make Tolkien's world look like it's populated by people from modern day New York, how large the minority audience is for this material in the first place.
I always thought the Tolkien fanatics who would flock to series like these were white geeks who spent their adolescence reading. In other words, people like me, although I was a girl, and the vast majority of fantasy and science fiction fans were boys.