alt Hacker NewsThey found having round icons made people look at the center, rather than the edges and corners. Since the UX relies entirely on where the user is looking, this made it more reliable.
I remember reading it in the HIG when VisionOS came out and everyone was complaining about the shape. I went looking to see if there was a reason, and there was.
That's interesting, but I think this is solvable in better ways. If the VisionOS icon grid doesn't have a voronoi hit map, then IMO they're doing a stupid. There's a _lot_ of space between icons in the grid. It should be plenty of distance to reliably determine that you're looking nearer to the center of a particular one.