The Seventies were the days of using convenience foods to imitate elegant dishes that used to take hours to do. If you could find a way to use Cheese Whiz, Jell-o, etc. or get it canned, frozen, or freeze dried, that was considered wildly superior to using fresh ingrediants. Yes, there were those who followed the Moosewood cookbook, but they were the minority, and most people scoffed at such crunchy granola vegetarians (says she who uses her Moosewood Cookbook and one of its follow-ups, The Enchanted Broccoli Forest, all the time).
I well remember that sometime in the Seventies, Jell-o came out with this new dessert called 1-2-3 that was made just like ordinary Jell-o gelatin, but wound up as this funny parfait. One layer was gelatin, one was sort of puddingy, and the third and top layer was like Kool Whip flavored and colored like the rest of the parfait.
You can't get 1-2-3 anymore, but it would be fairly easy to replicate (albeit probably in a slightly messier form) with a box of pudding, a box of gelatin, and a tub of Kool Whip.
If you want to know what a lot of cooking in the Seventies was like, you can always turn on Semi-Homemade with Sandra Lee on the Cooking channel. She terrifies me, but her attitude towards food is pretty much the one that reigned in the mainstream of the Seventies: use lots of convenience foods without consideration of cost or quality, booze everything to death, and cover your table with lots of co-ordinated junk.