The use case would be for transactions between individuals. A friend working at a large industrial firm told me recently that crypto would solve a problem that they have in Asia: orders are often done during auctions from the producer, and require instant payments; however the payment rails take two weeks to clear a transaction. Crypto would fix this.
The fact that it's not widespread doesn't mean that there isn't a usecase.
The fact that it's not widespread doesn't mean that there isn't a usecase.