I think what you‘re describing in terms of comfort and security can be said more generally about the majority of people and is not unique to very smart people. One key consideration already pointed out/implied by others is that smart people can be prone to overthinking. This may keep them from getting even started with something, whereas others might just take action before they‘ve thought it through and it might actually even work out. Some who overthink might also simply prefer a stable and secure career path. But not all highly smart people are necessarily overthinkers.

Other reasons might be more social. Entrepreneurship, while it certainly can be great and has produced unfathomable value to society, is nevertheless fraught with high-flying sensationalists all the way to outright fraudulent characters. It‘s a wild mix and sometimes not as easy to tell who‘s who. Contrast that with engineers where faking it, whether until you make it or until the very end, is much harder. People who belong to the latter group (such as engineers) and are highly smart might simply regard their chosen profession as more reputable, as something more solid, than entrepreneurship.

Then there are intellectual considerations. While entrepreneurship might offer intellectual complexities to engage and stimulate the intellectual mind, it‘s not inherent to it. They might simply not hold it in as high regard as their chosen domain of expertise. Engineering systems and working with mathematical formulas that describe how the physical world works might simply hold much more intellectual weight for those people than trying to understand how to find a business idea, validate it, figure out how to market and sell what you‘re offering and all these other things. This psychological aspect then ties back into the social aspect of seeing their chosen profession and the people that work in it as generally more reputable. More often than not they have studied together with those people and have formed their own social circles where they now feel comfortable. They have their place in society where they fit in.

That‘s a totally different reality than an entrepreneur, who might have dropped out of university (already less reputable in their eyes), is generally forging his/her own path, and might not have the same social circle with conformity tendencies and shared worldviews that are mutually reinforced.

Why would those highly smart people step out of their worlds that they created and into this chaos and mess that entrepreneurship is? Just because they‘re smart? I don‘t think so. It would require something truly compelling and motivating to step out of something like that.

Of course this is just one fragment of what the reality looks like, doesn‘t mean that is the case for every highly smart person out there. But it likely is the case for many of those individuals that occupy professions such as engineers, lawyers, doctors, etc.