Lies, damned lies and statistics.
Any number of factors can be brought in to consideration, average age in Africa is younger so more likely to survive but health care is of a lower standard so more likely to die.
More older people in Europe with chronic health conditions so more likely to die but better health care so less likely to die than a similar case in an African village.
Europe has good reporting and monitoring so the figures look worse than Africa which could actually be worse but we don't have accurate information.
Back in the 1990s when AIDS was the scourge in Africa, projecting the figures indicated that there wouldn't be enough people to bury the bodies of those who were dying in such overwhelming numbers. Economies would collapse as there wouldn't be enough workers left to keep things running.
Covid will simply run free in developing countries until an effective level of vaccination is reached. Poverty and overcrowding mean lockdowns and social distancing won't work. A rich country can tell its citizens to stay home for 2 weeks and pay an allowance for the unemployed to buy food with. A day labourer living in an African shanty town with neighbours a few feet away, poor sanitation, a family to support and no income won't be able to stay home as part of a mass lockdown to break the virus.