If nostr is truly decentralized, there can be versions of it like this, whether or not it is added to the repo most people use for NIP specs. And nostr is truly decentralized. Ergo, someone can develop altcoin zaps for nostr. Whether or not it can be added to the main repo is simply then, assuming that nostr with altcoin zaps is defined as part of real nostr, the determining factor of whether the main NIP repo is the one true NIP repo.