I would think, in absence of other evidence, that investing in microoptimizing sleep and stress would have more benefits than any language or tool choice. So i

I would think, in absence of other evidence, that investing in microoptimizing sleep and stress would have more benefits than any language or tool choice. So it's not just 8 hours, it's also midday naps, circadian rhythms, it's letting people sleep when they need to. And you didn't even mention stress and there are of course myriad ways to improve mood levels and reduce stress. And obviously some of that stress will come from your choice of tools and methods, but again, we have little evidence as to which tools and methods produce the least amount of stress. It's not what you do, or even how you do it, it's the circumstances in which you do it that have the greatest impact on your ability to do it well. Work 80 hours, work 5, play 50, dig ditches, cure cancer - doesn't matter, fix sleep and stress before worrying about the little things.