nostr:npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6 by forcing users to use a lightning (that's what I see on iris.to at least) wallet like for example zbd or alby, isn't nostr helping to centralize btc? why not supporting regular lightning invoices? is there a technical reason?