> not really surprising first countries to leave fossil fuels behind are also countries with mountains and rivers

What's surprising is countries sharing natural resources are among the pioneers, despite the geopolitical implication... like Ethiopia testing the Egyptian waters by building dams on the Nile.

Maybe you should lookup when these damns were built. I wouldn't be surprised if in 1970 there were also 9 countries who didn't use any FFs. Same 9 countries of course. If you can build hydro you do. Problem is, we already have them everywhere they can be. And even now, hydro is only about 10% of all electric power production worldwide.