Nostalgia is a funny thing — how it fixes on a past of a certain age, and only on certain aspects of that past. For example, I fondly remember writing on early computers, particularly on a Kaypro with a tiny screen that was black on which amber or green letters glowed.
Now this experience can be yours, but on the widescreen of your modern monitor. Dark Room (an avowed copy of the Mac program WriteRoom) commands your whole screen, paints it black and lets you focus on your writing free of the discractions of menu bars, desktop icons etc. The Mac app lets you change your background and text colours to suit your preferences — some like it blue — but I haven’t tested the Windows version to see whether it, too, has this degree of flexibility.
There’s some merit to this simplicity, I think. Word processors are absurdly “heavy” for what most of us use them for most of the time. And how we do like to fuss over formatting as a distraction from the hard work of thinking and formulating the right language. And then there’s the fact that it’s easier on the eyes, I think, to have the text be bright rather than the monitor background.