I’m always fascinated when someone equates profit with intelligence. There are many very wealthy fools and there always have been. Plenty of ingredients to substitute for intelligence.
It certainly doesn't hurt when the government profiles and grooms intelligent people out of Stanford SRI the dark side, Harvard, hands them an unlimited credit card and says, "Make this thing that can do x,y,z." and then helps them network with like-minded creators and removes any obstacles in their path. One has to at least admit that was a contributing factor to their success as the vast majority of people do not get these perks.
Intelligence probably IS positively correlated with success, but the formula is complex and involves many other factors, so I have to believe it's relatively weak correlation. Anecdotally I know about as many smart failures as smart successes.
You can be a wealthy fool who inherited money, or married into it. It is also possible to be a wealthy fool who was just in the right place at the right time. But I would guess that people who appear to have "earned" their money are much less likely to be wealthy fools than those who appear to have inherited/married into it.
We see this all of the time. Business makes successful bets in one area and tries to make bets in new area and fails.
Once you achieve wealth it gives you the opportunity to make more bets many of which will fail.
The greater and younger the success the more hubris. You are more likely to see fools or people taking bad risks when they earned it themselves. They have a history of betting on themselves and past success that creates an ego that overrides common sense.
When you inherit money you protect it (or spend it on material things) because you have no history of ever being able to generate money.
Neither necessary nor sufficient.