I am ambivalent about the Come and See ending, when we see Hitler's ascendancy in reverse. It's interesting inasmuch as it suggests that the boy has not lost his humanity, as he wouldn't kill Hitler as a baby. On the other hand, along with that sculpture of Hitler that they carry, it doubles down on the movie's fixation with Hitler as an antagonist. This is not complex enough. Furthermore, the movie was commissioned to commemorate the 40th anniversary of Victory over the Nazis. Knowing that—and given some of the heavy handedness, like the final speech by the Nazi (which I liked in an exploitation movie kind of way), the footage of the Holocaust survivor, the tediously abject suffering (which I was fine with) and the final scene in the forest (nevertheless, well shot)—it can be viewed as agitprop/propaganda.
Overall, however, it was compelling and immersive, and occasionally, darkly funny and scary. And cinematographically, it was excellent.