How much of the development in PV tech is linked to developments in other technologies, and how much is due to dedicated R&D on PV's? My personal understanding is that basic science is the main long-term driver, while directed R&D into a specific field is important for short-term gains in efficiency, but will tend to reach diminishing returns if it goes beyond what is enabled by basic science.

Economies of scale is more of a fixed saving on top. This may have helped take the cost per kwh of solar from $10 to $3, but the scientific development was what made it possible to go to $0.1.

In any case, PV prices are already very low. We are reaching a point where installation and maintaince are becoming limiting factors, and where storage is becoming the primary bottleneck.

Development in storage (batteries and hydrogen) already has so much momentum that building out some nuclear power would not threaten it.

Solar panels have barely improved since the 80s. What drove down cost, and continues driving down cost, is purely manufacturing volume.

New PV tech, like perovskites, might carry prices down further once the learning curve for Si levels off, but we are not there yet.

There is no "storage bottleneck". We just don't have anywhere near enough renewable generating capacity to justify diverting capital from expanding it to building storage. Diverting capital to boutique nukes, and to coal while we wait a decade or two for the nukes, would be far, far worse than that.

When we do start building out storage, vanishingly little of it will be batteries.