accessibilityChildren

This element's accessibility descendants: the union of accessibilityElements() (how the tree actually links together once inside it) and subviews (how to reach into it from an arbitrary starting UIView).

Both are needed because an accessibility root isn't necessarily attached to the view you start from — see this file's leading documentation for the Compose case that proves it. It is a union and not a concatenation: an element that appears in both lists is one child, and returning it twice costs deepestAccessibilityHitPath an exponential amount of repeated work (see the body).