Baseload is the minimum level of demand on an electrical grid over some timespan. Providing that baseload with solar or wind is not as cheap as hydro, coal, natural gas or nuclear.
The quoted prices for cheap solar energy don’t include storage. Solar plus storage is still expensive.
If you only look at the days when catches are high then it is the cheapest method to produce food. If fish are your primary source of food, and every day you don't get enough you will have to eat expensive imported food, you food cost over the year can be quite high for a primary fishing nation. The fish will still be cheapest, but as a strategy it is somewhat expensive or carry a high risk of starvation.
Nations will build as much solar/wind as there is peak demand, because it is the cheapest energy when it produce. Nation will also build coal, oil and gas power plants in order to be there when those solar and wind aren't producing. Economically that is the cheapest way to produce a stable energy grid. Environmentally it is far from the best. Falling solar and wind prices reinforces this model.
[1] https://www.oregon.gov/energy/facilities-safety/facilities/P...
https://www.carbonbrief.org/solar-is-now-cheapest-electricit...
New solar is now often cheaper than keeping a coal plant running
https://www.theguardian.com/environment/2021/jun/23/most-new...
And we should expect solar to get even cheaper.