The memory layout can be better this way depending on how the fields of a strict are laid out. It also gives the data better locality.

Let's say you're iterating over position coordinates of some set of objects in a game. With an array-of-structs you can lose ou on cache locality if unrelated fields are nearby. If you use a struct-of-arrays you get cache locality advantages anytime you do something like "iterate over this 1 field for each object"

The latter approach is called data oriented programming btw, and seems to have been around for a while. Andrew Kelley gave a good talk about it recently while using Zig: https://media.handmade-seattle.com/practical-data-oriented-d...