My two cents: I took the Elixir + OTP course, and found it to be a just-good-enough hands-on exercise, with just enough 'try adding X' exercises to feel comfortable sliding into the language. The presentation may not be everyone's cup of tea, but I found it to be just hammy enough to be amusing, and the back-and-forth format helped turn demonstrations into dialogues, which I find much more effective for exploring edge cases and reasoning behind a language.