NAME table differences between MacOS and Windows

1

When exporting a Black instance, the NAME table IDs are different when platformID=1 for old MacOS and =3 for Windows. Eg,

<namerecord nameID="4" platformID="1" platEncID="0" langID="0x0" unicode="True">
  Family Black
</namerecord>
...
<namerecord nameID="4" platformID="3" platEncID="1" langID="0x409">
  Family-Black
</namerecord>

Why is this?