That's verisimilitude. We were doing that with representational art way before computers, and even doing stipple and line drawing to get "tonal indications without tonal work". Halftone, from elsewhere in the thread, is a process that does similar. When you go deeper into art theory verisimilitude comes up frequently as something that is both of practical use(measure carefully, use corrective devices and appropriate drafting and markmaking tools to make things resemble their observed appearance) and also something that usually isn't the sole communicative goal.

All the computer did was add digitally-equivalent formats that decouple the information from its representation: the image can be little dots or hex values. Sampling theory lets us perform further tricks by defining correspondences between time, frequency and amplitude. When we resample pixel art using conventional methods of image resizing, it breaks down into a smeary mess because it's relying on certain artifacts of the representational scheme that differ from a photo picture that assumes a continuous light signal.

Something I like doing when drawing digitally is to work at a high resolution using a non-antialiased pixel brush to make black and white linework, then shrink it down for coloring. This lets me control the resulting shape after it's resampled(which, of course, low-pass filters it and makes it a little more blurry) more precisely than if I work at target resolution and use an antialiased brush; with those, lines start to smudge up with repeated strokes.