Because we are able to extract useful information from colorized output, being as it is an extra dimension of information output; I for one don't get an urge to pass a sort of of societal judgement of the high/low artistic worth of the use of color which may further increase efficiency. ¯\_(ツ)_/¯

Color is indeed very useful for terminals. But it seems to me that fish takes the use of color to an exaggerated, very unpleasant, extreme. It feels overwhelming to my senses. Like having blinking text here and there. It fills the whole screen with a mix of normal and reverse text in several colors, just for simple stuff like completing an argument.

That's actually very interesting :) I personally love it and find it perfect. Concretely useful. I hope there's a way to tune it down.

You can customize the colors with fish_config

i've seen it, and it is indeed easy to tone the coloring down. The fish shell completion is amazing, I love it! Too bad the shell does not seem to support process substitution (at least not with the same syntax as bash or zsh), so I cannot use it for the moment.