There is no town, city, or administrative unit called "Kalahari" with a population. The Kalahari Desert is a ~900,000 km² semi-arid savanna ecoregion spanning Botswana (most), Namibia (east), and South Africa (Northern Cape).
Indigenous peoples: San (Basarwa) — hunter-gatherers, ~100,000 across the region. Bantu groups: Tswana, Kgalagadi, Herero — pastoralists/farmers. National populations in Kalahari areas: Botswana (~2.4M total, many in Kalahari), Namibia (~2.5M), South Africa (~60M)—but no "Kalahari census."
Botswana: Ghanzi, Kang, Tsabong, Hukuntsi. Namibia: Gobabis, Mariental. South Africa: Upington, Kuruman, Vryburg. These are towns in the Kalahari, not "the Kalahari."
The Kalahari is a biogeographical zone, not a political unit. Its "population" is ecological (species, biomass) and cultural (indigenous nations)—not a headcount. Treating it as a place with a single population obscures its complexity.