First demand isn’t flat, so 100% nuclear needs massive amounts of storage to reduce the number of nuclear power plants that would sit idle 90+% of the time. In the end something needs to take up the slack and nuclear doesn’t work by it’s self. If natural gas isn’t an option the only thing left is hydro which is limited or storage.

Your also trying to cherry pick numbers the Wikipedia article also lists “$164/MWh” for nuclear. I found the table you got those numbers from which included multiple estimates from 2018 that used data from 2015 and double counting very optimistic nuclear estimates. Frankly utility solar is already being installed at sub 2c/kWh in the US. 68$/MWh would be 6.8c/kWh which shows how far off your umbers are.

Anyway, I would be happy to see the power plant actually run that cheaply but your looking at very optimistic estimates for something that isn’t even online yet and is getting some serious subsides.

Having said that if you’re data is from “Source: IEA/NEA, 2015.” https://www.oecd-nea.org/ndd/pubs/2018/7441-full-costs-2018-.... I can understand why you picked those numbers.