lets say each person made 1 remittance a week
knowing that there are 144 blocks a day and a potential of 4000tx a block (with luck)
4000x144x7= 4 million users making 1 transaction a week.
which is not adequate for the 192million migrant workers (quoted by world bank), thats just over 2%
I guess most of them do not have enough skill to "go to exchanges -> purchase some bitcoin -> send them to another exchange in another country -> sell them for local currency". I have tried to teach one friend to transfer the fund from another country (she is a 37 years old professor) when she visited me, she said there is so much hassle and she will never do it again, she does not care about the expensive bank fee, she just want fast and easy process of use her credit card
So even bitcoin were used in remittance, it will be some large companies utilizing bitcoin and the end user would only notice the speed and fee advantage. However, if it is operated by large companies, then they are operating more or less like Western Union, have frequent clearing and settlement and do not need blockchai
See Abra & Align Commerce
I've been registered at Abra for a long time but it seems there is no progress
AFAIK they're soft-launching in targeted areas for now (Philippines being one of them)
As for remittances it does need a tech-savy person and one someone somewhat familiar with Bitcoin to really leverage the benefits of it.
Personally I use Bitcoin regularly to send money abroad using rebit.ph and it's saved me a great deal of money and hassle.