It doesn’t matter if supply sinks up 1:1 because demand doesn’t. If solar always produced the same energy evenly form exactly 10AM to 6PM EST for some parts of the day you could have an over supply of solar and at other parts of the day you would have an under supply. The same is true on the weekend vs weekday. Even seasonal power demand is less in spring and fall than summer and winter due to heating and cooling.

Though when selecting individual locations for wind, different locations favor different time of the day. And of course solar output varies significantly east/west and based on local weather conditions. That all gets modeled ahead of time and in practice get reflected in market rates.