It seems like imagination was more common in those days. There was no "digital" anything to lean on.
The live-action PBS idents from the early 90's were some of the best.
https://www.youtube.com/watch?v=5Ap_JRofNMs https://www.youtube.com/watch?v=PJpiIyBkUZ4
This mini doc shows the process:
https://youtu.be/Q7iNg1dRqQI?t=167
alt Hacker News
The live-action PBS idents from the early 90's were some of the best.
https://www.youtube.com/watch?v=5Ap_JRofNMs https://www.youtube.com/watch?v=PJpiIyBkUZ4
This mini doc shows the process:
https://youtu.be/Q7iNg1dRqQI?t=167