After some more research, it appears that the most important factors that determine whether you use your hands or not are:
Age. Older Japanese are more likely to use their hands. Tradition and all that.
Region. Because of course.
Price of sushi. High end sushi restaurants often frown on the use of chopsticks because it's not traditional.
The overall consensus in Japan seems to be "eat it however you want". Like many food-related ceremonies, the ones surrounding sushi seem to have largely faded away over time.
After some more research, it appears that the most important factors that determine whether you use your hands or not are:
Age. Older Japanese are more likely to use their hands. Tradition and all that.
Region. Because of course.
Price of sushi. High end sushi restaurants often frown on the use of chopsticks because it's not traditional.
The overall consensus in Japan seems to be "eat it however you want". Like many food-related ceremonies, the ones surrounding sushi seem to have largely faded away over time.