That’s part of the fun though. It lets them do massive epic story arcs without needing to constantly be writing around those consequences later on. Especially with stories that are so nonlinear and time travel oriented, every tedious plot would basically hamstring every future plot, unless you are willing to play fast and loose with the lore. Then you can really get creative, while sticking to a handful of “fixed points” in the lore, which themselves can also be changed if the plot is sufficiently dramatic.