MacOS now has app sandboxing. Sandboxing is extremely hard to get right. It's even harder to retrofit it into an existing system, because so many programs exis

MacOS now has app sandboxing. Sandboxing is extremely hard to get right. It's even harder to retrofit it into an existing system, because so many programs exist that just store files wherever they feel like, and you don't want the new OS to break all the old programs. And if the OS provides a "legacy program" mode, malicious apps will just use that. In addition to files, sandboxing has to protect against capturing screen pixels, getting keyboard events, doing network or device IO, inspecting the cut&paste buffer, and hundreds more things, all of which some apps have legitimate reasons to do. So the matrix of permissions gets very large.