Is the work of the early Elvis Presley, making recordings for Sun Records in the mid-50's, distinguishable from the work of the same singer in his recorded concerts of the mid-70's?
It's a difference of 20 years. The difference between early Beatles recordings and their final work is less than 10 years. Looking at Dennis Potter's early work in the sixties and comparing it with his work 20 years later is even more instructive. Very few people would want to admit they could not tell which came first, Vote, Vote Vote for Nigel Barton or The Singing Detective.
In the 16 years between Steven Spielberg's Close Encounters, with its off screen aliens and Jurassic Park with its very much on screen dinosaurs, computers had become big enough and powerful enough to be used for origination.