Oh and on a related note, you’re using the efficiency of thermodynamic conversion as a substitute for the “fitness” of the ATP synthase machine, which it is not obvious to me that it is.
I would not need persuasion that it is one component of it’s fitness, but it has to do more than not produce waste in the interconversion of chemical and mechanical energy. It also has to actually work at sufficient speed to produce ATP fast enough to drive competitive growth and division, resist denaturation and degradation to some degree, etc. etc.
All of these components contribute to it’s fitness, and so it is actually likely(or at least possible) there is some compromise between these different aspects of it’s function where it’s performance is sub-optimal, and that a higher-fitness alternative exist somewhere in sequence space, where it is 99.999999% efficient, but 15% more resistant to degradation(thus needs to be replaced significantly less often, saving energy in that way instead), and 1.05% faster(say).
If you do not know the efficiency, stability, speed, and accuracy of other ATP synthases, and how these components affect it’s fitness, then how can you claim to know how they are distributed in sequence space, and that this one you referenced is the globally optimal solution in terms of all attributes that contributes to it’s fitness?