Player agency is a tricky problem. Games have always had an advantage over other media since the viewer is able to take part in the story in a way not possible in books or movies. But writing a story isn't free. For every choice a player can make new dialogue or content may need to be made. How do we make a player feel like they are in charge while keeping the development costs manageable?
There are tricks to avoid needing to do lots of extra work to make your world feel "real".