Java, yes: I have worked on systems, as have others on HN I'm sure, where Java is the bottom level language: there's a JVM, and below that there's hardware, and that's the whole story. JS and Python, not so much. This isn't complicated: there is a general agreement about what "systems programming" is, and the only people who make a huge deal out of the divide between managed languages and unmanaged languages are, again, this weird embarrassing (tiny!) subset of Rust people. I think the Rust core team people must wince about these arguments.

It's not as if Java and Go programmers don't understand the value of "zero-cost abstractions" (a term from the same 1990s vintage as the first version of Java) and manual memory management. I don't see a lot of serious energy being applied to getting Go running in the Linux kernel. To my eyes, the only people who really seem uncertain about Rust's value are the "those aren't systems programming languages!" people. Rust is not good because we finally have a language to do systems programming in; it's good because it's a good, interesting language on its own merits.