Try thinking exactly how this would work. Foreign workers sending money to their home countries cannot switch to Bitcoin until either of the two conditions is met:
1. Bitcoins can be spent directly for goods and services in their home countries, or
2. Bitcoins can be exchanged to the local currency at the cost lower than existing fiat-transfer fees. Note, even if this condition is met, there would be a huge imbalance in the direction of trade - coins coming into the country, not going out. To balance things out, arbitrage/fiat exchange is needed, with all the old cost we are trying to avoid here.
Option 1 is the only sustainable option in thr long term, and we are nowhere close to realizing it.
That may be your take on it, but it don't make it so...
Option 2 is the no-brainer, as far as I can see. Those transfers into the Philippines are crazy expensive. Fees for: buying a remittance vehicle (money order, usually), transmitting it (postage + insurance, or Western Union fee), forex fee at the other end, bribes or taxes at the other end (pick one)...).
All that; versus sending bitcoin to a Philippine-enabled exchange (no fee), selling it (0.5 - 3%), and ACHing the local currency into a local bank account (the equivalent of less than a US dollar, one would hope). I don't care how you slice it - given a Philippine-enabled exchange ('enabled' means it doesn't necessarily have to be in the Philippines), it's cake.
That's where the money is to be made, too.
If you doubt that last, take a look at the adoption cycle of Skype. Skype was
made by Mexican immigrants into the US who wanted to phone home, but couldn't afford regular phone charges.
[n.b., please note that the article you cite points out that Mexico receives more cash from these remittances than the Philippines] And Skype - back then - was not a particularly noob-friendly piece of software: but they figured it out because they had a good financial reason for doing so.