It's not crazy, it's kinda hard to implement containerisation yourself in a proprietary OS kernel that you don't control... However, as of fairly recently, IIU

It's not crazy, it's kinda hard to implement containerisation yourself in a proprietary OS kernel that you don't control... However, as of fairly recently, IIUC Docker for Mac uses macOS's native hypervisor framework rather than relying on VirtualBox as it used to.