1. Using deaths as a metric;
2. Focusing on operational cost of a nuclear power plant rather than total cost (ie including capital cost). The total cost is borne out in the relatively high cost of nuclear power to users. If that point is even acknowledged, let alone conceded, it's just dismissed as the fault of government regulation or that scale will somehow magically solve the problem; and
3. Writing off disasters as irrelevant outliers because they're inconvenient to the argument. Less than 700 nuclear power plants have been built and we've had multiple huge disasters.
So are deaths a bad metric? And by "deaths" here I mean any form of the metric (eg absolute, per-kWh generated, etc). Because deaths doesn't capture the negative externalities and consequences of nuclear power. Chernobyl killed less than 100 directly. Who knows how many contracted various cancers in a wide area. But 1,000 suqare miles of land remains uninhabitable nearly four decades later with no real end in sight.
Deaths as a metric doesn't capture that, which is precisely why pro-nuclear advocates focus on it. Nuclear power has its own propaganda just like the oil and gas industry does.