Hmm…
macbookwh:~ bbarker$ ls -last /nix
total 0
0 drwxr-xr-x 2 root wheel 64 Nov 13 19:37 .
0 drwxr-xr-x 23 root wheel 736 Jun 3 08:29 ..
macbookwh:~ bbarker$ sudo rmdir /nix
rmdir: /nix: Read-only file system
macbookwh:~ bbarker$
Hmm…
macbookwh:~ bbarker$ ls -last /nix
total 0
0 drwxr-xr-x 2 root wheel 64 Nov 13 19:37 .
0 drwxr-xr-x 23 root wheel 736 Jun 3 08:29 ..
macbookwh:~ bbarker$ sudo rmdir /nix
rmdir: /nix: Read-only file system
macbookwh:~ bbarker$