Comically the use of curl | bash managed to shoehorn them in there, and there were the occasional terminal escape characters that could do funny and sometimes mischievous things.

There used to be something of a game of making specific files that would change screen colors or play songs off terminal bells, etc, tailored for specific terminals or command prompt windows. I remember a few short animated sequences using various backspaces and colors that only really worked if you could expect the text to be loaded at specific baud rates or in specific BBS software.

Weeeell... Ya say that, but:

Many years ago someone "infected" my computer with a "manual virus": A printed-out sheet of paper placed on top of the computer, telling me to delete all my hard drive's files myself, then photocopy the sheet and put both copies on nearby computers.

It was obviously a joke. But in the "modern" agentic era, the same thing in a text file is slightly more realistic as a threat...

You can block macros in Word, so you're only left with unformatted downsides?

No macro viruses but if your family lawyer uses some LLM-powered thingy in his workflow it might add a new dimension: prompt manipulation/injection attacks. A good spot to hide these would be at about ⅔ distance inside some wall of legalese at the beginning or end of a document since hardly anyone ever reads those.

I've known people one-shot by pure text, like Atlas Shrugged, The Communist Manifesto, The Bible, The Qur'an, The Selfish Gene, Godel Escher and Bach, etc. Don't underestimate text.