If you are wondering which language to learn next - stop what you are doing and ask yourself this question:
"Can I take data from a field, process it, pit it into a database and retrieve it again?"
If you can't do that, then you don't need to learn another language, you need to learn a stack.
Most business applications involve taking data, putting it into a database and retrieving it again.
Knowing how to say "Hello World" in 4 languages is not as useful as knowing how to perform a business process in one language.
PUBLICATION PERMISSIONS: Original video was published with the Creative Commons Attribution license (reuse allowed). Link: https://www.youtube.com/watch?v=wpLkLjK2kS4&t=61s