Basically, if you know how to competently edit an email, you shouldn't struggle in frustration at editing a big terminal command. I believe that some day there will be a terminal app you can sit a kid down in front of, and they're be able to fix a typo without any frustration or special knowledge. That day hasn't yet come.
I get the historical traditions for why terminal is the way it is, and I get why people who already know the secrets don't care to change it, but IMO it's time to move on.