Kitty

Slate has an amusing “review” where Kitty Pryde complains about the problems with the X-Men movie Days of Future Past. Most of the references aren't easily parsed without a full memory of the source comics, but there is this item of note:

And cooperation—teamwork—isn’t enough in evidence in 1973, where most of the movie takes place.  When future-me and Storm and Colossus and Bishop and Blink fight the good fight in the bleak future, we work together; our best moves are team moves. But for most of the rest of the film, there’s not enough teamwork on display. Our heroes take on bad guys one by one, or one on one, shot by shot, even when they’re fighting in the same place. 

Of course, in 1973 - forty years back - it’s the height of the Awakening. The people are going to be mostly Boomers (Prophet archetype) and Silents (Artist) - not fertile ground for teamwork. By comparison, 2013 would have Millennials (Hero archetype) for whom teamwork would come more naturally. 

(All the actresses who have portrayed Kitty Pryde since the first X-Men movie have been Millennials, although the other mutants mentioned above are played by Gen Xers. The actual writer of the review, Stephen Burt, is Gen X (b. 1971).)

Indeed, 2013 is fully in the Crisis, so the generational constellation -   young adult Heroes (Millennials), midlife Nomads (Generation X), elder  Prophets (Boomers) - yields a configuration that is known to work together well. No surprise that the two parts of the movie have this particular difference - sometimes, it's just the sort of detail that can make a story seem more realistic.