Are you saying a lot of older people in South Africa are dying of Omicron?
No. They are two things. 1) Absent. They fled the infected region and 2) vaxed. 60%+ of people over 50 in SA are vaxed — and since it is SA they didn’t get their vax until relatively recently, unlike the US who got vaxed ASAP in Spring/Summer. The immunity fade is not as far along there.