Uranium is $128.30/kg
After enrichment, conversion and fabrication that’s $3400/kg for 4.95% fuel.
At 36-45MWd/kg and a net thermal efficiency of 25% or $12.5/MWh up front.
With a 90 month lead time (72 month fuel cycle and 18 months inventory) at 3% this is $16.2/MWh
If the alternative to 50c/W solar is paying $20/W, you only need it to run at 2.5% of nameplate to come out ahead.
No It’s not the fallacy you describe