What's crazy about the punch card era is how much of that nonsense persists to this day... Actually it's not nonsense (because it made sense at the time), and it's actually kindof beautiful that some of those relics are around. Gives a kind hope to people hooked on the relic BASIC language, does it not?
I surely can't name them all, but one corpse we keep animated is ASCII. Sure we have a trillion unicode characters, but when I look down on my physical keyboard, its ASCII.
Then there's the 80-character limit that never went away. Terminal applications often terminate lines at 80 for a reason that traces back to actual terminals, as you all know.
Of course, I can't leave out horrendous way you need to code in COBOL. The punchcards are there in your face in a perverted digital way. Follow weird indentation patterns, blah blah. Just a bunch of yuck. The code was so damn verbose, and to rub it in, you end a line with a period as if you really were writing a sentence. Terrible. It was the Java of the 80's.
One thing that the kids will ask about is why the "save" and "open" icons are this weird plastic thing and this weird yellow thing. We'll have to explain "kids, before quantum storage was perfected, we couldn't write our data to the wall of a black hole like we do now. We'd save it on a magnetic plastic thing. Yeah, they broke. Oh, and 1.44 megs at best." And then you'd have to explain what an *actual* file system is... and when you're done, surely the kid will say "what's paper?"
