That's an interesting thought, but I suspect, if the shot below is anything to go by, that it is the pixel structure and perhaps a high degree of interpolation that gives it a certain look when off focus. This was a Fuji Finepix 40i with all of 2.4 Megapixels that I bought in 2001. The lens was probably similar in design to a mobile phone lens.
Another camera, the Ricoh Caplio GX that I picked up in 2004, (5.1MB) had a conventional camera zoom lens and may have been less dependent on the software to create a sharp and interesting image.
But still, I'd see the camera as attempting to draw out the maximum resolution and contrast possible from the glass - pretty much the standard it would have been judged by.
I think you could ask a similar question if you could compare the oldest Summicron 50/2 with the latest. The max capabilities of a 1953 model would likely provide a rendition and contrast glow that the newest version could not achieve, simply because of what one might describe as 'excessive' modern coatings.