No, the original WSL was a weird new thing where NT kernel-level driver actually serviced Linux system calls. IIRC, Interix still used same approach as origina

No, the original WSL was a weird new thing where NT kernel-level driver actually serviced Linux system calls. IIRC, Interix still used same approach as original posix subsystem (and Windows and OS/2 subsystems) of providing the interface as DLL that ultimately your application would be linked against.