Not planned, but a reflection of culture. If you consider broad concepts in movies (which are generally transcribed literature into motion picture), you'll see even more interesting trends.
I'll give an example. If you look at the top 10 movies of 2002, included in the mix are City of God, Star Wars: Episode II - Attack of the Clones, The Lord of the Rings: The Two Towers, The Pianist, and Harry Potter and the Chamber of Secrets. All of these have a common trope: individuals having to deal with foreign masses. Yes, I include City of God, even though it is set within a single neighborhood. But consider what the protagonist is dealing with: a refutation of the status quo of drug violence. What the audience comes to feel is that he is the norm and the drug lords or wanna-be drug lords are the invading foreigners. In all of the above listed movies, the invading mass is dehumanized. So how does the trope of the evil alien mass reflect the American culture of 2002?
There was a fear of invading Muslims bent on literal destruction of all Americans.
The trope we are seeing in movies in games of humans capable of leaping high into the air is a metaphor. It is not literal. It is a subconscious concern that human beings are about to be capable of short flight that enables that human to come down and attack specific people or groups. Those groups, of course, will likely be portrayed as the antagonists (even if they are the ones that start with the technology with the idea being that the antagonist had the technology and the protagonist stole it and now uses it against the antagonists).
The flying exoskeletons are a metaphor for the drones that appear to be on the cusp of saturating American society and culture. That's why Thor could fly in his movie, too.