If all you care about is typing a stream of letters and numbers, this is indeed so. But I very often need editing things, moving text around, selecting, alteri

If all you care about is typing a stream of letters and numbers, this is indeed so. But I very often need editing things, moving text around, selecting, altering words, copying and pasting. I need upper case and lower case, fancy punctuation characters, etc. Not that a proper Morse code mode can't be invented for that: vi gives us an example of such an interface, based entirely on letters and mode-switching. BTW Morse code is relatively slow to enter by fingers alone, the muscles are too weak for the mass. A proper entry key is fast because it uses muscles of the entire arm.