Nim's ARC thing is pretty different from blackbox GCs you have to poke with a stick like Go's or JVM's. It's pretty deterministic where additional calls are inserted by the compiler, and you can use --expandArc or look at the generated C.

As a single anecdote -- I've studied Rust before and it's been a while. Pretty familiar with C++ move semantics stuff. I decided to read the Rust book again while also learning Nim simultaneously; and I had an entt wrapper and graphics rendering in Nim without GC before I finished getting through the borrow checking chapter in the Rust book.