It is a huge barrier. After all, you can't run a train without train tracks. The same goes for cryptocurrency and the blockchain in the sense that in order for it to expand there needs to be a grid (internet , cell towers, computers, etc)
Also, since many of these countries don't have many resources or capital for these projects, foreign investment will be needed. This could be done by transferring capital into the most developed regions in the country or countries and then expanding the infrastructure outward. That in itself is a problem as investments from the top(corporations, billionares) often come with nefarious intentions along with the often shady governments that run the countries. Thanks for reading the post.