Why were the characters all kids?

In the OG movies, average crew age was 30-35. This one felt like they were more like 20-21 tops. Felt kinda like the Maze Runner or Hunger Games, where you have a bunch of kids trying to survive. It was a big turn off for me; just doesn’t feel realistic for a trillion $ company like Weyland to have kids with zero seeming experience handle a space mission.

I missed the first 4-5 mins so I might be missing something to the story?