I don’t disagree with your main point, but in the context of this article:

1. When we’re writing a research paper, they have to stay tightly focused on the subject at hand. That’s the nature of scientific research. In this case, they were setting out to investigate whether individual climate denial was caused by people not wanting to change their own actions. That is, whether it was motivated reasoning (or avoidance of cognitive dissonance as I might have put it), or something else. My work has always indicated it’s purely politically and socially motivated).
2. You’re not going to get the corporations to do anything while you have half the country believing it doesn’t exist or isn’t important. You’re right about what needs to change, but that’s not going to change until the laws change. The laws aren’t going to change until there’s a mass mobilization to get that to happen. So we’re going to have to win them over, and on the basis of this kind of research we know that their resistance is not coming from motivated reasoning.