Edit: Adding this addendum to reply to commenters themes.
These Bitcoin-based transfers are not on the Bitcoin blockchain but instead actually happening on the Lightning network- the transfer fee is close to zero.
In addition to the fees of traditional remittances, there are sometimes additional significant inconveniences- for example some have to travel by bus to the city where the Western Union is located.
The current extended Bitcoin drawdown probably doesn't effect things much. Users generally convert their BTC to dollars in the Chivo wallet app the country uses to avoid the volatility.
Despite all the theoretical advantage for remittances, adoption for remittances is still very low, with 11% ever using the app for this. It may be in part because using the government app means the remittances are known to the government and can be taxed as income, whereas cash goes unreported. https://www.howtogeek.com/801982/bitcoin-is-legal-tender-in-...