If you ever used multiple clients you know that not all clients follow all Nips. Some clients are very basic in terms of Nips they support and that's actually fine. Some clients use Nips that haven't been merged.  But if you want to do something and somebody else is also doing it, use a NIP and be interoperable with each other.  

I couldn't care less if pronouns are part of a nip or not. A client that wants to add pronouns could have done it before it's in the Nip and if a client doesn't want to add it, it doesn't have to. 

If two or more clients decide to add such a field (whatever field) it still makes sense they use the same name for it, doesn't it?

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