Wouldn't it be better to just transfer the BTC to a UTXO the nsec can unlock?
That's exactly what it does. The npub and taproot addresses are the same key.
ohhh I missed that! Nice! Let's go!
I'll add a sentence in the NIP to make it clearer. Thanks for the feedback!
Added: "Note: that taproot address and npub are interchangable addresses with a different prefix. Sats are transferred to a UTXO the nsec can unlock."
nostr:nevent1qqswtd2p6uwdh3kfph88yeqf9ccx3qvawl66wwtlh9dzwmylfuk0cvqpz9mhxue69uhkummnw3ezuamfdejj7q3qxtscya34g58tk0z605fvr788k263gsu6cy9x0mhnm87echrgufzsxpqqqqqqzddwqht nostr:nevent1qqsrxp52tx73dgqf4g9da0pldzh3s7pv82yk9l8u3fam2tvjwtgx3fcprfmhxue69uhhyetvv9ujuam9d3kx7unyv4ezumn9wshsygx70mx3u2tk56km9la97ndcrf7cztytke5c4gqdeu08dtd4tm7kg5psgqqqqqqsyygrcs
Example: https://nostrapps.github.io/taproot/