And it's not like we haven't seen that the average person can make better decisions because of education, than medieval age lets say. Maybe we just need faster ways to improve the population.
We should differentiate knowledge from intelligence or wisdom. Knowledge can be fake, misleading, or contradictory. We have more knowledge and access of information than medieval age typical Joe, but do we have more intelligence or wisdom?
To make the comparison easier, do we have more intelligence and wisdom than Plato (whom I am certain that we possess more knowledge)?
1. Science. To the point that average joe understands that the prediction of climate change is concluded from the same scientific methods that helped us finding cures for diseases, inventing computers, and sending people to the moon. Science is not always perfect the same as we dont always have perfect cure for some diseases at the moment. But that is the best we can do for now, and it's the work of many experts over many years. So it is logical to either believe it or contribute to it scientifically, financially, auditing-wise, or something else. After all we believe in scientists not because that they have the title, but because we believe in scientific methods, in scientific approach.
2. Social science. Pure science is about causality. Social science can teach us value, what is good, what is bad, and happiness. Then we can discuss whether not acting upon climate change will make you more happy or less happy.
To be educated IMHO, we should care about reasons of what they say more than the title of what they say. It is not unusual for scientists to draw wrong conclusions from the the right reasons, and those right reasons can help you draw your own right conclusions.
When each of us can maintain our own set of knowledge/conclusions under a set of consistent reasons, then the society will be much more resistant to any kind of appeal to authority/popularity logic fallacy.