Order doesn't matter .. Foundation always predates a building :-) But we create foundation for the building .. not the other way around ...

Nostr was not created with zaps as the purpose of its existence, It was created for free-speech and censorship resistance. Zaps developed organically when users started pasting invoices for other users to pay and it was eventually added into the protocol itself as an event kind.

Bitcoin was created as eCash system .. but turns out it is digital gold .. so .. whatever be the motivation of #nostr creation .. the real function that it fulfills in society shall be determined by future users .. Btw .. it is not new .. Columbus set out on search of India ..but he landed in America .. In creative fields , it always happens .. so in business .. you start on something but pivot as the opportunity space becomes clear

You say that as though being an eCash system and digital gold are mutually exclusive, or as though Satoshi had no idea Bitcoin would be a good store of value when he created it. That said, I do believe systems can become something other than what they were designed for. I don't see that being the case for Nostr, though. At its core, Nostr is still a permissionless and censorship resistant protocol for communication (free speech) of which zapping is just one expression. The ability to zap anyone you want with small amounts of sats is really just another form of free speech among the many that are enabled by Nostr.