Africa doesnt often have the kinds of mass gatherings that we do here regularly"
Which Africa? South Africa where tens of thousands gather for football or horse races? Malawi where a gathering of 5,000 to protest politics have become the norm in cities and where it's not usual for weekend weddings to have a gathering of 1000 each wedding? Egypt where gatherings of a few hundred will be broken up to avoid "unrest"?
We actually do have. Perhaps not thousands as in Cheltenham festival but weekly weddings, dances, funerals etc
Why aren't we hard hit as Europe? No one knows. The epidemic is not over yet so may be the worst is yet to come for us. May be genetics and environmental factors operating differently there than here, less global travel, may be the BCG vaccine as others thought (not proven), and all the other factors others have said.
As to isolated villages in Africa. There aren't many left that isolated "thanks" to development "aid" and changing demographics.
And no it's not just that there is poor recording and reporting (yes there is but...) If there were hundreds or thousands dying we would have known by now. Citizen journalism is very alive in many African countries, relatives etc. We don't exactly live in bubbles entirely dependent on weak governments. Asia? Quite a few have experience with SArs and as much as some in developed countries find it hard to accept, have done an excellent job at providing quarantine, tracing, testing, PPE. It's an interesting question though because most countries at least in Africa are not in proper lockdown or isolating because it's impossible. For now, we are just grateful that for once we are not the ones dying in numbers. After all, preventable diseases kill more of us each year than those dead from covid globally so far.
We can only wait and see in 2021 after bona fide studies and when it's all under control