They've come to realize it now because there are huge companies that are coming in and some governments that are in favor of it but the counterpart is to regulate transactions that happens inside their country.
Is this really an indication that the Big banks will be more accepting towards Bitcoin?
Not that really but more banks would come to have their own service but first, they're likely to buy chunks of bitcoin and might treat it as their bitcoin reserve supporting whatever service that they might come to it that's related to bitcoin.
They can't deny the fact that big financial institutions and big companies are continuously buying large chunks of bitcoin or integrating crypto in their system. And I believe, they feel that they are being left out if they will not join the pack. They are now seeing that even with their advice to be careful in dealing with crypto, people are continuously patronizing it. As an example given above by
suzanne, if more and more people will discover this advantage of bitcoin in cross border payments, a lot of people will use this method and traditional payment methods like WU will slowly lose their clients.