Hence with 1.7 billion people staying unbanked, added to the increase of people who don't rely on banks, Bitcoin provides them with numerous options why they should use bitcoin for different purposes like sending money to relatives in different countries at a very low fee.
The chances that the 1.7billion unbanked individuals will choose to only adopt bitcoins without using any kind of normal fiat bank. There is barely anyone who uses bitcoins and don't have any bank account. Even if there is the benefit of making transfers over long distance easily with bitcoins, not all your beneficiaries are using bitcoins yet, so they still need the banks sometimes.
Bank marketers are also very hardworking, they can infiltrate these places where there are many unbanked and convince them to open up bank accounts faster than the story of bitcoin will reach them.