The age of the average African is significantly younger than the rest of the world. There's a lot of variables to account for, you'd need a proper study, not just a single data point, to determine if omicron is significantly less deadly than older COVID variants.

As for GP's claim that vaccines saved a lot of lives, that's very well supported at this point https://www.commonwealthfund.org/blog/2022/two-years-covid-v....