An explanation of the ending which makes logical sense

I just watched the movie, and immediately rushed to these message boards to help me understand the meaning of its end. Having read through many topics dealing with possible explanations of the ending, several of them quite fascinating, I find it surprising that a very obvious one hasn't been touched upon yet by people here.

The movie cuts to dark at the very end, and then opens again in 'reality', where we observe the main protagonist alive and well while a camera crew is busy setting up the scene of the marching soldiers which took place earlier on in the movie.

But besides the fact that the quality of the video is clearly less than the images we as viewers saw before, the surroundings depicted also have significantly changed. The movie is filed with dust, rocks and sandy mountains, clearly meant to be metaphors of the absence of life. (I might return to this opening post to further elaborate on this when I've more time). But when we are 'transported' to reality during the ending scene, the outside world has visibly changed, showing lush, green grass and colorful flowers. Not just that, but the images of laughing soldiers in the rays of a bright sun also seem to indicate a change of the season. A possible indication of the change of mood of the protagonist himself?

Now, wouldn't it make sense to conclude that the purpose of this scene is to show that the protagonist has in fact survived, and has decided to make a film out of his existential crisis? Shooting the scenes he witnessed when he was by himself.

(And yes, I agree that this explanation is perhaps disappointing in that it isn't as intellectually stimulating as others)