It’s simply one of the most productive languages. It actually has a very strong type system, while still being a dynamic language that doesn’t have to be compiled, leading to very fast iteration. It’s also THE language you use when writing UIs. Execution is actually pretty fast through the runtimes we have available nowadays.
The only other interpreted language is Python and that thoroughly feels like a toy in comparison (typing situation still very much in progress, very weak ORM situation, not even a usable package manger until recently!).