Many of those old recipes on the notecards relied on heavily processed, shelf-stable industrial ingredients from a century ago that few people would use today. The recipes were commonly disseminated by companies as a form of marketing for their product. We have unimaginably superior access to diverse and fresh ingredients today compared to many of the recipes that e.g. my older relatives used.

Modding those recipes to replace the dependency on heavily-processed ingredients with the fresh, less-processed comparables readily available today often produces good results, though it does take more time.

Archive has a bunch of older recipe books. This [1] is a collection just from the 50s which would be primo processed time (mass canning/etc just after WW2). I could not find a single recipe with anything like what you're describing.

[1] - https://archive.org/details/cbk?and%5B%5D=year%3A%221950%22&...

Blessed is the person who decided to exclude recipes from copyright law. They will forever hold a place in my heart.

That’s a limitation of your source. Several recipes that I’ve seen passed down from that era were like this. Many of those recipes have an origin that can be googled.

I am an accomplished cook and I have a lot of recipes passed down a century or more first-hand. Many have the property I described. I know many other people with similar family recipes.

Just because you’ve never heard of it doesn’t mean it doesn’t exist.

Most of the product types you're describing didn't meaningfully exist until the 50s (which is why I used that era) as WW2 greatly expanded production of crap food and subsequently led to a wider public introduction. So having family recipes using them from a century or more would be quite odd.

Beyond that, what do you think is more representative of recipes of the past? A selection of hundreds of recipe books with thousands of recipes, or the family recipes of yourself and some acquaintances?

That might have been the case in the US but definitely not everywhere.