Having lots of hydro resources native to ones State doesn't count much towards deploying or leading in green tech. Being a State with lots of precipitation that is easy to capture and with low relative population doesn't give that State an inherent title of being more green.
The green title would come from developing and deploying green tech like solar and wind turbines, battery storage, etc.
FWIW, I am not against large hydro or nuclear and they have plenty of merit.
But California is making leading progress with deploying solar and wind and eliminating coal and even reducing natural gas. That is something many other places so far have struggled with. Germany, for example was leading with solar, but still uses a lot of coal.
Keep in mind that the population of California is larger than the sum of (VT+ ID + WA + OR + ME + SD) or (ME + VT + IA + KS + OK + SD + ND). So adding any one of those States renewable or renewable + hydro production to the CA grid barely makes a dent. Conversely, if those States had to support the population of CA, their percent renewable or renewable + hydro production is rather small.