They provide constant demand in low consumption periods which makes it possible to have a stronger grid when indeed there is a spike in demand due to external c

They provide constant demand in low consumption periods which makes it possible to have a stronger grid when indeed there is a spike in demand due to external conditions like a heat or cold waves... something which will keep happening more and more (and more extremely) if you listen to climate scientists. The keywords are scaling and stability, if you prefer to piss this money away on building plants that will work at 50% capacity for years you essentially pay for the rest of the capacity with no other utility, that's bad governance.