and how much of gold price is in your opinion value of material itself? Strip out that material price and you have speculation price. Price of Bitcoin is mostly that speculation price + instead of material some mathematical properties.
Mathematical properties don't provide economic value.
The demand for bitcoin is almost all speculation, and a tiny bit is for purposes of making clandestine payments, paying ransoms, and such.
Probably incredibly little. I have not in the slightest looked into it, but based on bitcoins properties, I'd guess that it doesn't suit 99.9% of Africa. They use cash and frequently use mobile phones for transferring cash etc.