For me it took a tremendous amount of work to somewhat understand the OTP stuff though. Its one of those languages where I can never be confident about my implementations, and thankfully it has features to check whether you have stale processes or whatever. A language I am humbled by whenever I use it.
I love saying this but OTP is a really roughneck standard library. They just added shit to it as they needed it without apparently putting too much consideration into the organization, naming, or conventions.
It makes it very powerful but very disorienting and experience gained with one part of it often does not really prepare you for other parts. Usually each specific tool was created by someone who used it immediately, so it's all reliable in its way. But there is a lot of redundancy and odd gaps.
Elixir's almost extreme attention to naming, organization, and consistent convention is almost as far as you can get from this approach too. It's fun to have them in the same ecosystem and see that there are actually pros and cons to each approach.
Thank you for this post and I'll add a note for people who are seeing this and are maybe discouraged about learning Erlang/OTP/Elixir.
I generally agree with you that learning Erlang stuff can be daunting.
I will say that many things worth doing are not easy! Erlang and the whole OTP way of thinking is tough to learn in part because it is genuinely different enough from everything else that is out there that one's odds of being familiar with its conceptual underpinnings are low.
If you have trouble learning Erlang (and OTP specifically) it's not because you're dumb, it's because Erlang is different.
Learning Erlang is not like learning any other dynamic language you've learned. Learning Erlang is closer to learning a bespoke operating system designed to build reliable low-latency long-running systems. It's a larger conceptual lift than going from one dynamic OOP language to another dynamic OOP language.