It's wise to care about the climate. It's wise to investigate human behavior's effect on climate. It's also wise to question investigations, their results, and especially their conclusions.

I don't know what a downside to getting off fossil fuels would be but its not hard to imagine some. Take this article for example : https://www.abc.net.au/news/science/2016-06-15/what-is-an-ic... I seriously doubt the scientific basis for the statement "The Earth is due for another ice age now but climate change makes it very unlikely" but it's one idea.