I've been writing code for close to 10 years now and I see this and feel like what a beginner would feel trying to understand assembly code. Or someone hearing a similar but new language.

Looks to me hours of work and learning got abstracted as under the hood "magic".

It's like saying: Oh, so I've been weight training for the last 17 years and I should tell you Olympic silver is not too hard, see?

Am I right in my thinking? or is learning to be this proficient with the framework not as time taking for a novice developer as I think it to be?

There's no magic. It's functionality that's made possible by the BEAM. It's just one of those things that came out of realizing how powerful the runtime was for handling certain types of problems.

When you combine a couple of those bits together, you end up with this.

The only modern web problem that Elixir isn't ideally suited for is heavy number crunching. Otherwise it gives this amazing balance of efficiency, scalability, reliability, maintainability and capability that can't be replicated in any language that has a shared memory model.

I would caveat that in a couple of ways.

First, suppose you have a web app where some requests involve heavy number crunching and others don't. In web frameworks where 1 request ties up 1 OS thread, a burst of heavy requests could gobble up all your available connections. Phoenix would use one cheap BEAM process per request, and the BEAM's preemptive scheduler would ensure that other requests are answered in a timely way and that all the heavy ones continue to make steady progress. So although the heavy requests might be completed more slowly than in another language, the overall system would remain more responsive.

Second, if you have need for heavy computation or data structures that work better with mutability, it's possible to (eg) use Rustler (https://github.com/rusterlium/rustler) to implement that part in Rust. See https://github.com/rusterlium/rustler for a story about doing this.