Every time this point comes up, ultimate conclusion isn't the CLI is bad or can't be improved, but the VT220 and similar emulation that's holding things back. Any person who has developed a terminal emulator can attest to that. There have been and are attempts at a much better CLI, but until we drop the legacy baggage, we can't have nicer things, at least in a sane way. But if we do that, we don't really have enough incentive to use the newer tools. Its a catch 22 after all.