Nuclear in current designs doesn’t really fill this need because it can’t be economically spun up and down to match renewables’ down-periods. Current designs allow some load following but only a very limited amount, and the capital costs are still so high that it doesn’t pay to run the unit at partial output. Maybe someone will find a design (SMRs possibly) that changes this, but it will take at least a decade or two to get deployed and then it will be in competition with battery tech that exists in 10-20 years, which will probably eat all the low-hanging profitable use-cases.