I think one answer comes by asking why the scammers love it because the answer that it’s easier and safer for them to transfer large amounts without getting caught. That’s also shows why there’s relatively little mainstream usage. If you’re comparing it to all of the other options people have, it’s unappealing – harder to use, slower, riskier, more volatile and expensive – but the scammers and ransomware gangs accept that because it’s still better than traditional money laundering.