Other ECS implementations might not, but Bevy does come with a system scheduler. You register systems (functions that operate over the components) and, through their parameters, Bevy's scheduler decides how to parallelize the registered systems while avoid data races.
Other ECS implementations might not, but Bevy does come with a system scheduler.
That's an ecs data structure and a system scheduler. If I make a vector and a system scheduler, vectors don't suddenly have system schedulers, they are two different things.
You register systems (functions that operate over the components)
That's just adding a function pointer to a field.