Per megawatt of generated energy, coal releases significantly more radioative waste into the environment than nuclear does.

It’s not meant to be “fair;” it’s meant to shock people with how ridiculously bad burning coal is. Think about it: it’s crazy that a trace-element unused byproduct of coal production is a pollutant being produced on the same order of magnitude as the thing in nuclear power that’s actually producing all the power. Until people read it, they’d probably guess that coal either produced no radiation at all, or many orders of magnitude less than nuclear, but nope. And on the other end of it, if that tiny fraction of coal’s pollution output is enough to rival all of nuclear, I think it helps put a finer point on just how much worse all the rest of it is.