The only issue - but it has nothing to do with climate - is how to position your company so that it financially benefits from state-organized plunder (whether it's through direct fiscal spending, or though indirect theft such as subsidies).
Can someone provide an example of a startup actually impacting Earth's climate, or showing any indication whatsoever that it could, without employing direct or indirect use of force? Let me guess: you can't.
So pretend that it's about entrepreneurship? At least several commenters (such as https://news.ycombinator.com/item?id=20883900) say it makes no sense to try and instead argue in favor of the use of force (ie the government directly telling you want to do) which is indeed true - it's a use case in which "climate entrepreneur" is just an overhead. If you want to solve a problem with more government, you might as well get these unnecessary startups out of the picture - less overhead, more resources for the problem solvers in the government.