Golang or Rust don’t fit the bill?
Ahh they are looking at Rust next.
Go is not a systems programming language. Rust does fit the bill.
IIRC Go was originally designed to be a systems programming language and can technically be used to that effect, even if (relative to Rust) there are few projects using it in that capacity.
Then why does it include a garbage collector? Garbage collection is totally unacceptable for a systems programming language.
D has a garbage collector, and yet you can use it for operating system development: https://dlang.org/areas-of-d-usage.html#operating_systems
Lisp has a garbage collector, and yet you can use it for operating system development: https://github.com/froggey/Mezzano
Go has a garbage collector, and yet you can use it for operating system development: http://lsub.org/ls/clive.html