[ksec]

>but I would never call a GC language a systems programming language....

Lilith: x86-64 OS written in Crystal (github.com/ffwff). [1]. And Crystal has GC.

[1] https://news.ycombinator.com/item?id=21860713

[ac130kz]

Probably they meant that GC introduces a certain level of uncertainty, whereas OS or "systems" programming leans heavily towards manual handling (except when the compiler allows to avoid it, not the runtime).