Revert "[subset] also obfuscate nameIDs 16, 17 and 18, if present"

Actually, I have changed my mind. I think there is no point in keeping name IDs 16, 17 and 18 as duplicate of the (obfuscated) name IDs 1, 2 and 4.
I'll file a new PR and will simply drop those name IDs 16–18.
Sorry,

C.