It may seem odd that Athena, a robot designed to find dreamers and distribute pins, is equipped with all of her combat options, but it should be remembered that historically, people have been known to respond violently to things that challenge their worldview.
The rocket flying out over Paris wipes out all electronics. No phones, no cars, no pacemakers. It could also disrupt hospitals and planes.
Then what were the lights on Earth? When Athena, Frank, and Casey were above Earth there were lights clearly visible.
Also, hospitals have backup generators that kick on when the main power cuts off. Seeing the main power cut back on after a few seconds, the backup generator wouldn't even cut on as a result.
Remember when Nix says that we are hopeless because we head towards self destruction. He is not lying, guess what post apoc movie came around the same time and made more money than Tomorrowland? Mad Max: Fury Road.
Which, ironically, was also an optimistic movie in its own right.
Remember when Casey first got her pin, got transported into a wheat field, walked around for a second...and then hit her head against the police station wall? And then, remember later, when she got her pin back...and fell down the stairs of her house? It seems like the vision of the futuristic city only affects your vision and hearing, while keeping your physical body in the real world, where it can fall, hit other people, run into things, and generally be harmed...and then, at the end of the movie, a bunch of people are given those same pins. People in the middle of the city, on a hiking trail, in a construction site...
"I'm the future, Frank Walker" says a pre-teen girl android. OK, she means she is an enabler of the future sought by Plus Ultra. But taken differently... Do I need to explain why some people will want to buy robotic little girls once they are (soon) invented?
Is it really that hard to believe humanity fell to desperation, fear, and hopelessness after World War I?
such as the real-life flag of the Kingdom of Spain.