Ohhh! That's interesting! I'm in the process of reading.
Ok. I read it. Whew! Talk about a quick, tour de force of film criticism (as in Ebert and Roper, etc.)
I know one thing I didn't pay attention to in the movie was that Thanos is wearing the glove on his left hand, but the Avengers wear it on the right hand. I just knew that the Left was evil ... but goodness gracious!
Anyway, you asked me previously, could it be "the falling away." Well, I'm assuming you haven't seen the movie. What happens is that Thanos snaps his little fingers in the 'power-glove' he has, and makes half of all people, life-forms, or whatever, throughout the entire universe...disappear. But not for their own health, mind you. This is different than what we find in the Bible, as interpreted among those Christians who believe in a Dispensational Rapture, where such an event is DEFINITELY
for the health of those so "caught up."
So, I don't think any of the motifs in the Avenger's movie represent populations of the world becoming evil. Rather, Marvel has basically taken some religious motifs, symbolized them with a superhero "coating" [a mythologization of sorts] and embedded those motifs and religious parallels into the story line, knowing that the audience with catch some of the similarities as well as some of the contrasts. And this is typical of superhero comics, as the fictional 'stuff' that it is.
The downside is that these producing companies may have political and ethical predilections that they ALSO sew into these movies, so along with some interesting values (like perhaps those of Captain America), there also comes whatever is currently PC in the outside, real world worked into these films as well.
So, there's a mixture of social and philosophical motifs in these movies, some of which are compatible with the Christian faith.............and some that are not.