It sounds like this may be done in an effort to improve the reliability of eye tracking in VisionOS when dealing with checkbox, not Apple just throwing the design book out the window for no reason.
>In general, prefer circular or capsule-shape buttons. People’s eyes tend to be drawn toward the corners in a shape, making it difficult to keep looking at the shape’s center. The more rounded a button’s shape, the easier it is for people to look steadily at it. When you need to display a button by itself, prefer a capsule-shape button.
>In general, prefer circular or capsule-shape buttons. People’s eyes tend to be drawn toward the corners in a shape, making it difficult to keep looking at the shape’s center. The more rounded a button’s shape, the easier it is for people to look steadily at it. When you need to display a button by itself, prefer a capsule-shape button.
https://developer.apple.com/design/human-interface-guideline...