Ruby is exactly as versatile as all those other languages you list. It was made before Rails was, and it can do everything eg Python can. It's not very popular anymore outside Rails but eg lots of people did APIs in Ruby using stuff like Sinatra. I personally did lots of CLI utilities in Ruby. It's really nice for stuff like that.
Yeah not sure why this is downvoted it is true, a lot of the open source tooling for ios is built in ruby and plenty of people build scripts and cli tools in ruby.