The remittance companies like WR and transferwise are already circling the drain. Yeah, they can do it cheaper than WU and MG, but they also get hammered by fraud because they cut corners.
That said, to play devils advocate, as long buying and selling steem is primarily bitcoin mediated, bitcoin is going have a huge advantage in cross border money transfer.
As someone who works primarily in this area (moving international money) things like instantaneous transactions (versus waiting 30 mins) or no transaction fee (vs a fee of a few cents on thousands of dollars) just arent significant enough to overcome the first actor advantage.
All that said, they have to actually get transfers that reliably work before any of this "disruption" becomes an issue.