I'm more charitable in my interpretation of the average human.

There's a difference between being greedy or selfish and taking the path of least resistance out of necessity.

As far as being "idiots," I just want people to cut people some slack. It can be easy to despair about all the things people don't know or are misinformed on, but take a step back and look at how big and complicated the modern world is. There is a massive amount of knowledge that makes up our society, more that any individual can ever personally know. So instead we build a kind of collective knowledge through our relationships with one another. You might not have gone to the moon, but someone else did, and they shared their experiences with the rest of us. Most of the people involved in the supply chain needed to build a computer almost certainly don't know how a computer works or how to design and build one from scratch, but that's ok because through everyone doing their specific part of the process, it still gets made and we get to use it.

However, a critical component I think people forget about this collective knowledge is trust. You need some reason to trust that the information someone else has given you is accurate or that the product someone else made for you works. Without the tools and expertise, you have no way to personally verify every claim made, so you must decide whether or not to believe the source of the claim.

There are all sorts of reasons that you might form such an information trust relationship with another, some more valid than others. You may know the person personally and believe they wouldn't lie to you, but they may also be wrong. You may know that the person is accredited by some reputable institution, but that just kicks the can down the road to whether or not you can trust the institution. Ultimately this isn't about people being stupid or uneducated, it's about how people choose to trust various sources. What makes one more valid than the other?

One way to somewhat break out of this issue is to build up a foundation of core knowledge through education that can act as a framework for evaluating how reasonable claims are, even if you don't have specific knowledge about them. You might not know the details of how someone's supposed perpetual motion machine works, but if you know the basic physics rules about energy, you'd know such a thing is impossible. But the problem with this is that it once again kicks the can down the road back to how you originally learned the information that goes into your framework. If you start with incorrect information, you will not be able to properly evaluate later claims. For example, if you grew up religious and were taught that god created the universe and then someone comes along and tells you that actually there was a big bang that created the universe and that evolution is responsible for the development of life, then those claims would seem absurd to you. I wouldn't call you inherently stupid for rejecting those ideas based on your prior incorrect understanding. It's incumbent upon us to find ways to build that trust such that we can educate you in the correct information.

When it comes to climate change, there are various sources of information that also overlap with each other. Scientists, news media, governments, NGOs, corporations, etc. They all have different expertise and motivations. They all use different methods to communicate with others and build trust. It may seem obvious that the output of the scientific community should be relatively trustworthy if you have previously learned the processes involved in generating scientific consensus, but if you aren't familiar, you might not get why one scientist says this, but these other scientists say this. If you thought you could trust your gov or news outlets, then them telling you climate change isn't real seems trustworthy. It may seem obvious why corporations can't be trusted to someone who is familiar with how capitalism works, but if you don't have a firm understanding on that and say, grew up in a country that absolutely idolizes businesses and business people, then you might look at these successful companies/CEOs and think that they must know what they're talking about.

There's a reason the right is constantly attacking education. There's a reason why businesses spend tons of money on advertising, lobbying, etc. They know what they need to do to keep people from agreeing with each other on correct information. You can lament that people are led astray by them, but it clearly isn't a trivial endeavor.

The point is, throwing your hands up in the air and saying that people are just "selfish idiots" is little more than doomer shit. If that's true then there is genuinely no hope. But if you understand the systems and dynamics at play in producing the world we see, you can better work to change it. How do we do that? Fuck if I know, but it's what we have to figure out and do.