Here is an illustration of backwards progress. Yes, I know, all these pictures are reduced to 72 dpi for display on computer-- these are illustrations. To give you real samples to analyze with me, I'd have to post some files that are very, very large, to show what the pictures look like, for example, at 400 dpi. However, anyone with an actual collection of photos can verify my argument. You can see that the black and white photos from the 50's and 60's have better resolution than the Instamatic or Polaroid shots from the 60's, 70's, and 80's.
Kodak Brownie Picture, 1950's. Large negative format = decent print.
Brownie Picture - 1960's still quite decent.
35mm black and white, 1960's: very sharp, good depth of field.
Brownie colour photo, 1960's.
Instamatic Picture, 1960's.
Pocket Camera, 1977. Ever try enlarging one of these sandbags?
Polaroid Picture, taken in 1980's. Yecch. To the turtles too.
35mm colour, 1992