I like switching gears, I truly don’t find it an advantage using the language for both. Have separate languages makes the distinction between backend world and front end world very clear. Also the backend code is mostly data manipulation and the front end code is mostly rendering so there is very little overlap in similar functions for both. The separation helps keep things tidy in my brain.

I much prefer not having to write JavaScript everywhere, not every problem is a nail and not every solution requires a hammer.