Fair point. I should mention that I'm not a Nim expert, and am not defending its design. It's true that 'nil' appears in Nim under both of its pointer types (GC traced "references" and untraced "pointers") -- which is unlike, say, Rust's safe references vs. unsafe (nullable) pointers. So 'nil' is not simply a systems level construct; otherwise you might expect Nim to have nillable pointers, but not nillable references.

You need nil/null when doing systems work -- and Nim is capable of that -- but I don't know the rationale for allowing 'nil' in higher level language features.