You need grid connected storage where you have (unpredictable) renewables. That doesn't negate the benefits of Nuclear baseload power. In an ideal mix, you need both, and also Gas for emergencies. One is not better than the other, they have different roles in a balanced grid.
Nuclear has a hard time existing in a net with dominant renewables during most of the year. Down-regulating nuclear absolutely kills its profitability. What you want is power plants with low capex that can be profitable with just a few hundred hours at full capacity per year. For example you can burn hydrogen.
Plus, related (storage), you do not want to put hydroelectric in water reservoirs targeted to population consumption, as you could find out one summer that the reservoirs are empty, the result of such water being used with the intention of generate electricity, or even used as inertial stabilizer for renewables.
This is the moment were at the news you read "There's a drought because it isn't raining" and similar excuses, when in reality your five years of water's reservoirs become reduced to half -or one third- due they focused the electricity production over the population real water demand.
I mean, hydroelectric needs at least two level’s reservoirs, one to generate electricity (or even exclusive two level's reservoirs with water pumps for this), and the next one, absolutely untouchable by the electric companies, targeted as water storage for the population/agriculture, the classic more than five years reservoir, for real.
Nuclear has the same issue as (unpredictable) renewables, it is incapable of cost efficiently following the demand curve. As a result, just like renewables, it requires a form of dispatch-able power to complement it (gas, batteries, etc). Solar and nuclear fill the exact same role in a balanced grid - cheap non-dispatchable power.
Or at least nuclear would if it was cheap, but since its costs haven't fallen the same way that the costs of other energy did... well new nuclear buildout really doesn't have a good role at all right now, it's just throwing away money.
Solar and nuclear complement eachother fine - because their shortfalls (darkness for solar, high demand for nuclear) are mostly uncorrelated... a mix of non-dispatcahble power with uncorrelated shortfalls helps minimize the amount of dispatchable power you need... but batteries have made it cheap enough to transform non-dispatchable power to dispatchable power that nuclears high costs really aren't justifiable.