nostr isn't designed with the goal of being a platform for payments. Bitcoin works well because Bitcoin works well in almost any environment
nostr is a worldwide notepad where people can write and post stuff, not a vehicle for monetary transactions

so I don't think it's worth the effort to try and make more currencies viable in nostr, that's just not the point. but the beauty of it ts that if you want to integrate whatever coin in nostr, you can just go and build it ⚡️