I think there is a conjunction of factors at play. Only slower film available means no clear images of action. No digital copies means that most pictures have h

I think there is a conjunction of factors at play. Only slower film available means no clear images of action. No digital copies means that most pictures have had LOTS of time to deteriorate before being digitised and reproduced. Most people see images from the 30s as a one copy of a picture the great great grandpa had in a shoebox kept in a moist cellar and no negatives to recover. I think most people would have had contact with old pictures from newspaper and books that did not prized image quality so you mostly see bad quality pictures with low dynamic range. The most important pictures of the olden eras, in an artistic setting, would also be experimental photography which is not necessarily concerned with sharpness and traditional qualities, so you see weird stuff. And, the main culprit, as for most of society misconceptions. Movies and tv shows, you have to age and crap out a picture to look old. I am certainly that the screwed up videotape effect will skew a lot of the expectation of old footage from the 80s-90s. Put all of that together, there is where I think the expectation comes from. I have the book Great War, Photographic Narrative. With images from the first world war, the quality of some of the images is outstanding. Those same images would've look terrible on old mass produced books and newspapers.