Starting a business is really challenging, as anyone who has tried it knows. Trying to make the finances work in something ephemeral is likely even more challenging. In any case, most businesses fail so ephemeral business is sort of the default unless you succeed.

There are individual businessmen who ride different business waves (like getting into frozen yogurt a little over a decade ago). But the skill those people have is in marketing and raising money and that transfers pretty well to different business types. There's also a whole world of business outside of tech that most of HN is not familiar with, and many of those people do extremely well for themselves. They also tend to be less idealistic and more focused on the money, which probably helps with adapting the business over time and figuring out what product/service the market actually values.