Well, I mean for beginners on-Chain Bitcoin but I've seen some tools enable Monero too.

Overall, replacing zaps with something like a https://coindrop.to/ ,BTC Payserver, Bitcart, Bitrequest, or some other type of implementation where people could send different currency types as The Nostr ecosystem grows, and begins to foster Bitcoin Cash, Litecoin, Dash, Zcash, etc. users.