What are you balancing if not human growth? And how do you plan to do that?
If it’s unsustainable population growth there will eventually be some catastrophic environmental effects and the population will be reduced to a sustainable level. Of course living during that reduction could be a rather unpleasant experience but it probably also won’t last too long.
If it’s already sustainable everything is fine.
If someone said they pick up trash on the side of the road to help the environment you wouldn't say the logical conclusion of their ideology would be that they become the unabomber
[0] https://solar.lowtechmagazine.com/about/the-solar-website/
I think what I'm honing in on is the idea that hand cranks produce very limited, often interrupted power and are relative low-tech, both of which are directionally the right way for us to be putting our efforts.