Parameter 'type' expects a netdev backend type

When using QEMU on an M1 Mac with Mac OS 11.1, I see this error message when trying to enable networking for a guest:

Parameter 'type' expects a netdev backend type

Example command:
qemu-system-i386 -m 700 -hda <Windows XP HD file> -netdev user,id=n0 -device rtl8139,netdev=n0

What should happen is networking should work when issuing the above command. What actually happens is QEMU exits immediately.