Most of these unbanked people are from the rural areas and such regions provides lots of workers and most of them work outside the country. If a person in diaspora wants to send money back home and he realizes that his loved ones are unbanked, what will he do? So with BTC, such people may escape from the remittance high fees. BTc will open the minds of many people who receive it. Everyone on the internet require some private and fast Ttransaction, it'll surprise you to know how electricity is everywhere including the rural area.
~snip~
I would not agree that the fees for sending money from abroad are so big, because we had already had such discussions on the forum before and I think @stompix showed some examples on WU transfer. In addition, the volatility that BTC has should be taken into account, because the one who sends must first buy BTC, and then the recipient must sell it to get cash.
Even if we talk about LN, theoretically the value of BTC sent in a very short period of time can change +/- 5% or more. Of course, the higher value will not bother anyone, but for someone who loses 5-10% by sending BTC it will certainly no longer be a good option.