The Japanese quite conservative and usually for good reasons. Move fast and break things and fail often isn't in their playbook.
You could argue that electric vehicles are the most conservative solution because we already have a national power grid, and there's a fairly clear path towards producing green electricity.
https://www.world-nuclear.org/information-library/energy-and...
https://www.bloomberg.com/news/articles/2021-10-22/how-paris...