Users can still add whatever they want to their profiles. I don't know why you are saying that a centralized committee is blocking it. Right now we already have 30 or so different fields on Kind 0 events. Just five of them are defined on the NIP.
There are hundreds of kinds that were never defined as NIPs. This centralization idea you make of Nostr is so strange. I don't know if you are just saying things in bad faith or if you truly don't know how Nostr works.
The NIP is just an interoperability point so clients can understand each other and bounce ideas off each other. It is not a W3C spec.