Who's arguing against evolution? Humans evolved to use our brains to help us develop ways to prevent having to go without food for extended periods of time.
"Not only are we deeply wired to function for long periods of time without food"
So the body doesn't collapse after x number of hours without fuel. Your body also has the ability to generate its own heat when it's cold. Does that mean that it's desirable or ideal that we deliberately use these abilities? Does it mean that there is no harm or risk in doing so? I'm not saying that there is or isn't; I don't know.
"but when you haven't eaten in a while your mind becomes focused and alert"
This is sort of like the focus that you get when you're being chased by a wild animal or falling out of a tree. I don't know that seeking focus from sources like this is a great idea, but YMMV.
"since your body thinks it needs to find or hunt food."
So maybe your body is telling you that fasting isn't such a good idea?
"I'm sure Dorsey isn't the only high profile/ functioning CEO who does multi day fasts each week."
I don't do multi-day fasts and I've lived for years longer than Dorsey.
The evolutionary angle isn't the reason why I believe fasting is a good idea - it's just a rebuttle to "there's no way you function well while fasting"... of course you can, it was likely the MO for millions of years of modern human evolution (or 100+ M years for mammals). It's as natural to fast as it is to fornicate.
Rather, my reasons for fasting come from the scientific literature, centered around autophagy, insulin control, sirtuin activation, visceral (organ) fat depletion, and troves of clear lab test results of benefits (albeit most on non human mammals).
Based on many comments here I think folks just haven't caught up with the longevity research of the last 3-4 years.
From what I've read, this "evolution" argument doesn't seem to hold much weight. If you take other apes as examples, they tend to eat much more, and more regularly than modern humans. Modern hunter-gatherer tribes do as well. So, I don't think there is reasonable evidence that our ancestors normally followed a feast-and-starve diet.
"Not only are we deeply wired to function for long periods of time without food"
So the body doesn't collapse after x number of hours without fuel. Your body also has the ability to generate its own heat when it's cold. Does that mean that it's desirable or ideal that we deliberately use these abilities? Does it mean that there is no harm or risk in doing so? I'm not saying that there is or isn't; I don't know.
"but when you haven't eaten in a while your mind becomes focused and alert"
This is sort of like the focus that you get when you're being chased by a wild animal or falling out of a tree. I don't know that seeking focus from sources like this is a great idea, but YMMV.
"since your body thinks it needs to find or hunt food."
So maybe your body is telling you that fasting isn't such a good idea?
"I'm sure Dorsey isn't the only high profile/ functioning CEO who does multi day fasts each week."
I don't do multi-day fasts and I've lived for years longer than Dorsey.