> Most implausible-sounding ideas are in fact bad and could be safely dismissed. But not when they're proposed by reasonable domain experts.
Off the top of my head, I vaguely remember that the latter half of the careers of many "greats" like Einstein, Fermi, Erdos were riddled with pursuing directions which bore no fruit (to this day).
I don't quite think that crazy bets work on "average". On average they fail. It mostly so happens that crazy bets are on "average" taken by people with a network that can attract able and passionate people, who can see through an idea to its conclusion. This is where experts come in.
Experts often rely on validation by their "community", and by the nature of community dynamics need to upsell. They naturally attract the kind of people needed to execute crazy ideas. But then attracting such talent also has a corrective effect on the originally crazy idea, such that it has a higher chance of succeeding by minimizing the blind spots, the unknown unknowns.