IME a lot of the learning curve is functional programming, shortly followed by OTP. If you've ever worked with a functional language picking up on the OTP abstractions (eg. GenServer) is a small hill to climb in order to become effective on a day-to-day basis.
That said, with every new language comes idioms, tools and libraries that one has to learn, but this is true for all languages.
That said, with every new language comes idioms, tools and libraries that one has to learn, but this is true for all languages.