The comparison of photosynthesis vs energy generated by solar panels isn't very good, because it neglects the whole biology of the organism, which is optimized

The comparison of photosynthesis vs energy generated by solar panels isn't very good, because it neglects the whole biology of the organism, which is optimized for things other than maximum photosynthetic output. For example, leaves are often targets of herbivory, so a plant might want to make a tradeoff [1] of less efficient photosynthesis for better herbivory defense. Or, it might be too costly to do photosynthesis, which requires the input of carbon dioxide, water, and light. In a very dry & hot environment, to get enough carbon dioxide into the leaf, the leaf will lose water by having its stomata open. Google "leaf economics spectrum" for a quick tutorial (the concept isn't 100% correct but it's a good starting point). Compare the leaves of tropical plants (say a banana palm) to arid plants (mesquite tree). [1] I use this a teleological shorthand for "the selective environment has weeded out species that happen to fall on the wrong side of the tradeoff."