I’m genuinely worried that we’re the last generation who will study and appreciate this craft. Because now a kid learning to program will just say “Write me a terminal spreadsheet app in plain C.”

The thing is, any generation can say something similar. Just look at the article: it manages to produce and describe the creation of a simple spreadsheet, yet the code and accompanying description would only fill a small pamphlet.

There are various reasons for that, and those reasons extend beyond leaving out vital functionality. While C is archaic by our standards, and existed at the time VisiCalc was developed, it was programmed in assembly language. It pretty much had to be, simply to hold the program and a reasonable amount of data in memory. That, in turn, meant understanding the machine: what the processor was capable of, the particular computer's memory map, how to interface with the various peripherals. You sure weren't going to be reaching for a library like curses. While it, like C, existed by the time of VisiCalc's release, it was the domain of minicomputers.

I mean, can the current generation truly understand the craft when the hard work is being done my compilers and libraries?

Which is somewhat akin to downloading one today. If, however, that same kid started small, with a data model, then added calculation, and UI and stepped through everything designing, reviewing, and testing as they went, they would learn a lot, and at a faster pace than if they wrote it character by character.