A fun problem on a Mac is that if you're using APFS for your filesystem, if it fills up, you can't delete any files. It's caught me out a handful of times, and each time, the only way to recover is to reboot, and thankfully I've had more free disk space after a reboot.
I'm not going to try to understand the logic as to why APFS requires free space in order to delete files (via any method, including dd)
I'm not going to try to understand the logic as to why APFS requires free space in order to delete files (via any method, including dd)