This is the saddest misconception that keeps getting trotted out in opposition to nuclear power. People use Fukushima as an example that nuclear power isn't improving in safety, when Fukushima was an old plant around even before Chernobyl. They didn't redesign the plant or substantially alter anything in the wake of Chernobyl. It was built to withstand loss of power, a massive earthquake, and a tsunami all at the same time. The fatal flaw was that when the plant was sited and built, scientific consensus was that a tsunami that large in that area was flat out impossible. As the science improved, no one went back and understood the implications on the design of the seawall that was now known to be inadequate.

Fukushima was a failure, and an expensive one at that, but in terms of the death toll almost all of it is solely from evacuation of the surrounding area and only one case of lung cancer that was likely caused by the accident. There were zero cases of acute radiation poisoning.