It appears that these figures take into account _just_ energy production. They don't seem include the mining, enriching, construction of reactors, disposal of waste, decommissioning reactors, etc. When mining low-grade ore (which isn't uncommon, and is becoming more command as high-grade ore becomes more scarce), nuclear plants are as inefficient as coal-fired plants [1]. Nuclear advocates tend to ignore the full system, and focus on where nuclear shines: power production. The setup to get to that point is extremely costly.
[1] https://www.stormsmith.nl/i05.html