Why would it be? You might want to implmentent authentication, without any need for HTTP 402.
Specs work best when they are modular and loosely coupled.
So a 402 spec can be built on top of NIP-98, say with NIP-981 etc. Same with 403 for access control.
Sorry, i am mixing my html codes.
That being said, the client-side flow for authentication and payment are similar. Server responds with a auth request or a payment request, the app receives, makes the Nostr event (or pay the ln invoice) and sends it back "automatically" (in case of the invoice, with confirmation from the user).
I just don't want two client flows using separate communication standards for these features.
