There is not a single reactor on this list with an operation factor (proportion of hours delivering any energy) over 85%.

Storage, backup, and overprovision are part of any system. 24/7/365 nuclear is a myth.

Once you acknowledge that reality it becomes a calculation of total costs vs. total emissions abated. VRE is about 5x as effective by this metric without even using any strategy other than minor overprovision, existing w2e/hydro, and fossil fuel methane backup, because generating even the mythical 100% green energy starting in 20 years is far worse than generating >80% green energy starting in 2 years.

Even if the long term plan is all nuclear (this doesn't work with commercial technology, there's not enough U235) it's still optimal to max out the VRE pipeline first. The VRE will pay back before your nuclear reactor is done just by the money saved on coal and gas.