Note there's also macOS-related reasons to use the different modes: Reduced security mode is needed to boot into outdated macOS installs (specifically, I belie

Note there's also macOS-related reasons to use the different modes: Reduced security mode is needed to boot into outdated macOS installs (specifically, I believe this is "outdated, insecure, at install-time"), along with loading kernel extensions (which aren't supported in full security mode on Apple Silicon). Permissive security mode is needed to boot into macOS with a custom XNU kernel. But yes, this is a significant change to iOS devices, but not to older macOS devices.