Irrationally optimistic people will tell you they have a device that defies the laws of physics (I mean hard laws, like conservation of energy or the speed of light), and investors will give them money. I have seen this happen enough times I'd actually have to stop to think of the correct number.

The point is both are disconnected from reality. What we need are people that aren't full of shit. There is a place between "everything is impossible" and "everything is possible" that works better for getting things done.