Spoofing fails on Mojave with no error message

Encountering this issue with a 2018 MacBook Air on macOS Mojave 10.14.6.

Running the following command fails without any status messages:
```
sudo spoof set aa:bb:cc:dd:ee:ff en0
```

I run the command, enter my password, and the command seems to complete. However, running `spoof list` reveals the Mac Address has not changed.

This issue appears to affect manually setting the address with `ifconfig` as well. Running this command also does not change anything and does not throw an error:
```
sudo ifconfig en0 ether aa:bb:cc:dd:ee:ff
```

Not sure if or how Mac spoofing might be disabled system-wide, or if something else is going on here. Any help is appreciated.