Windows' handling of command line arguments historically has been poor; even in 2019, Windows still passes arguments as a single command line string, which makes processing arguments error-prone and also results in unreasonable limits on command line lengths.
ArgX aims to fix this situation in a backwards-compatible manner, such that programs that use ArgX will be able to pass arbitrary numbers of arguments cleanly among themselves without worrying about how various metacharacters might be interpreted by subprocesses.