I'd also bet some money on that. Even at a residential level, the fiber rollout in many suburbs and few townships allows us to remain connected during the 2 hour planned outages. A lot more people are buying small UPS devices to power our routers and modems.
A lot of businesses continue to invest in solar, I don't think a cloud provider that's carbon-conscious would leave their operations to diesel generators and mostly non-renewable electricity (https://www.eskom.co.za/dataportal/supply-side/station-build...). The link is to the supply mix over the past 7 days.
I'm South African, working remotely for a US employer. We often joke that my colleagues' broadband is 3rd world while mine is 1st world, as it seems easier to get a good fiber line here than there.