I honestly doubt it’s in a global optimum, as evolution is easily stuck in decent local minima. Simple example: “C4 carbon fixation”, which allows photosynthes

I honestly doubt it’s in a global optimum, as evolution is easily stuck in decent local minima. Simple example: “C4 carbon fixation”, which allows photosynthesis to proceed with much less water available, only evolved ~30 million years ago. This was the revolution that allowed modern grasses to emerge, and thus changed enormous barren deserts into the savannahs that early humans made their home. Despite being such an improvement, this is not yet a “standard”; trees, for example, still use the “old” inefficient “C3 carbon fixation”. Despite photosynthesis having been around for hundreds of millions of years, fundamental improvements still happened just 30 million years ago. I would suspect that there is more that can still be improved.