Makes sense. Personally I sense it as a.... Vibrancy, I guess is the closest word. I might not always notice when I feel it/experience it, but I definitely notice it's absence. I find the computer analogy kind of comforting actually, because it means that things can (With enough consideration and thoughtful effort) eventually be made usable/accessible.
When I am feeling depressed the following two things happen, both of which I suspect are similar to what you (both) are describing - 1) Know the phrase, "Not a fan"? A common idiom used to express a negative emotion or feeling, but not intensely negative - more like a passive or background dislike as opposed to active and impassioned. When I'm depressed, I find I become "not a fan" - of myself, of anything I can do or create. None of it passes muster or can live up to my desires or expectations or hopes. Everything simply falls short, and I feel "not a fan" of my work (/myself). 2) No matter what options I have in front of me for "things to do," nothing is appealing. It is similar to "not a fan" in that nothing is overtly off-putting - I'm not like "Oh god no I would never do that!" - but I simply have no desire to do anything that I could do, even things I regularly enjoy and such. I guess I feel these things are similar to "greyed out" and "lack of vibrancy" because both of you seem to be talking about how things may remain present, or visible, or seem within reach or ability or grasp - but faded, diminished, lessened.