Natural gas can presumably be easily switched on and off to take up the intermittent 50% of the demand. So the realistic combined price is somewhere around $47.
Why then build nuclear at $97 ??
There is always a baseline need for energy, seems most sensible to me this comes from a modern, nuclear source and not the relics we rely on today.
The real reason to consider nuclear is that there is more than construction cost, there is also fuel cost. The fuel over the life of the nuclear plant is considerably cheaper than for a gas plant. Of course, even that isn't the whole story: I don't know how total operating cost and negative externalities balance out.
EDIT: I misread; it appears that those numbers are total cost per MWh produced, not construction cost. In that case, it appears that gas definitely beats nuclear hands down (ignoring the CO2 problem).
Yes, which is why you would want it for base load rather than responsive. If we invested in nuclear technology rather than condemn it all as a terrible venture we could produce far cheaper and cleaner nuclear plants.
Diablo Canyon nuclear plant in California is being shut down in a few years mostly due to environmental concerns but also in part because it can't be spun up and down easily to adjust for the output of the state's increasing mix of fluctuating solar and wind production.
We're headed towards a mix that looks like almost entirely renewables and peakers, or maybe eventually renewables and storage, if things like the tesla battery installation work out.