Not elected leaders in general, just elected leaders in our specific ecosystem of incentives for those leaders. For them to be acting irrationally, it would be

Not elected leaders in general, just elected leaders in our specific ecosystem of incentives for those leaders. For them to be acting irrationally, it would be necessary to show that genuinely solving problems is what they're trying to do, but people who put that above the negotiations and compromises necessary to be reelected do not survive or get promoted to higher offices. If we want to change the outcomes, we need to change what it takes for someone to be elected. And that will not happen as long as people believe that anyone who disagrees with them or behaves suboptimally just isn't thinking rationally.