Another issue is the volatility of crypto, cryptocurrency is subject to unpredictable changes in the market, For businesses, a 3 percent drop in bitcoin’s value can be big enough to generate a massive loss, and that’s a risk business owners are not willing to take.
https://cioafrica.co/the-truth-about-crypto-usability-in-nigeria/Africa is riddled with poverty, disease, and famine. Doesn't seem to me the issue is inherently with crypto, they just don't have the technological infrastructure to support crypto. I don't mean to sound crude, but isn't entirely dependent on countries with small GDP's to adopt crypto in order to make a significant impact on the crypto sector. And adoption of crypto isn't going to fix the government corruption either. It makes citizens' less dependent on corrupt government, but even with economic independence, government authoritarianism is inescapable.