Physically they can ramp down to 50% but generation is pretty much a sunk cost at that point so it makes the bad economics even worse. That would mean that you are paying of the order of $240/MWh instead of $120/MWh.

For comparison solar/wind are about $30-40. Levelizing with pumped storage pushes that up to $60-$70.

IIRC France and Germany almost exclusively use gas for load following. Even at current prices it's vastly cheaper than using a NPP to do it.

When capex costs more than other technologies plus storage, and it reduces your neutron economy and thus the life of your fuel it's just curtailment with extra steps.