If your thesis is that the masses aren't that careful, what you just described would not fit, because that's closer to "being careful" - sending or sweeping a bitcoin balance out of the Nostr combo client+wallet purpose-built to accept & manage on-chain zaps, or exporting/importing the private key from it as backup, into a separate btc wallet. What does this btc wallet look like, anyway? Is it a crapware wallet that people installed despite negative reviews from Gigi & company, that it only has one receiving address & forces spending reuse?