Great theory. Simple - but profound. Also got me thinking ... have long had this thing with Efficiency as a key driver. We're always aiming for the most efficient way to do something - you learn how to do something, then you learn how to do it faster/more efficiently.
Which is similar to the water flows downhill analogy - we're programmed to find/refine the path of least resistance.

And this is in line, if I understand him correctly, with what Jeff Booth argues, that a free market, a truly free market that uses real money, is always deflationary due to increase in productivity and innovation and by extension, efficiency. We're always striving for it. Particularly in free markets, that's the name of the game, greater efficiency and productivity.

There are instances of bad choices though. I've made em. Not in my best interests. I know that coz i regretted them.

With the person running into the fire, let's say it was too late, the stranger died, the person who ran in suffered 3rd degree burns, lost their lucrative job as a model ... then they got addicted to pain medication drugs, behaved erratically, whereupon their partner left them & they lost custody of their children ... & finally their home in the divorce settlement.

LOL! Or, a much simpler example but one that could not as easily be made into a TV drama, some dude has a bad day, gets drunk, and crashes into a brick wall at 90 miles an hour. Still, he was doing what was easiest for him. On a more serious note, there's suicide, someone ending their own life because that's less painful for them than the alternative.

Which is where Sapolsky's view gets interesting - there is all this massive accumulated stuff from the past that goes into influencing every decision in the now. He identifies childhood trauma as an obvious de-railing influence-factor on a person's decision-actions, but expounds that beyond our own lives - there's also this whole cultural history bearing down on every decision-action.
Doesn't leave a whole lot of room for free-will!

And this touches on another philosophical dilemma for me, and that is the logical conclusion that we don't really exist as individuals at all. We've touched on this before I think, but clearly our perception of ourselves as something 'individual' does not reflect reality, just the pinhole we experience realty from, our bodies. But of course, there's no such thing as one of anything. A single person could never exist, ever; therefore, it doesn't.

Which raises the question of whether there is an adjustment zone in a world without freewill?
A zone where you tend to make more good non-freewill water-flow decisions than bad ones? Where you sail through, as some people seem to do.

Hmm... interesting question. Or are our decisions dictated by our options? It all gets very chicken and eggy. And if we look at ourselves, meaning the human species as a whole, why do move as we do as a species? War, famine, still happening today. Why?

My limited gleaning from Sapolsky suggests this may be the default setting, but it's impacted by ... impactful events - which, by definition, are out of your control.

The other thing is, the path of least resistance implies that there is a force of Resistance - what's that exactly?

Yes! That really is a much better way of asking the question I just posted. What is the force?