Unfortunately, Tessa, you are mistaken. The distinction you have made is between slander and libel. The term defamation encompasses both. I thought you understood what I was saying without the distinction, but I can provide one if it helps.
You say someone is focused on “wealth building” and “has no understanding of how the current financial system is 100% responsible for the currest destruction of our planet, that is ignorance and it’s not very bright. It is also misinformed.”
First, Tessa, this is an opinion. You can have one and Jordan Peterson can have one. Insulting anyone who has a different opinion doesn’t seem very intelligent. Peterson talks to experts in their field on every topic from climate change, cryptocurrency, physics, religion, economics, etc. He does this multiple times a week.
Calling Peterson misinformed and ignorant is edging on arrogance.
The above link will take you to an interview with Michael Shellenberger. He is also the Founder and President of Environmental Progress, an independent and nonprofit research organization based in Berkeley, California. He advises policymakers around the world and has writings and TED talks that are viewed over 5 million times.
I suggest you read his work and listen to his lectures before offering future opinions on him.