Facts. Only attacks I ever saw were physical where the code would seek the drive head on Atari 810s repeatedly or strobe it or attempt force xt drives in and out of the landing zone to similar effect. obviously over time this is not good for the mechanism.
I don’t remember cpu therms being an issue until the mid late 90s - and then it was athlons. I could be wrong but I dont remember seeing CPU fans until the Pentium II cartridge but that is probably misremembering nostalgia.
80s was just robust against thermal - heck ataris had a giant aluminium shield over the mobo
I also heard stories of programming graphics card registers in a fancy way to trigger high frequencies in the CRT coils that could, again if the CRT was vulnerable, potentially destroy the coil. But this also relied on very specific hardware to pull it off.
A generic attack on such a high volume home computer or floppy drive like the C1541 would definitely have made the rounds back then in the computer magazines.
And the myth that developers deliberately put in code to damage or even destroy the pirates' computers can also be ruled out almost entirely, as (at least in europe) even back then there was a strong legal protection against deliberately damaging other people's property. I distinctly remember reading about this being debunked in the largest German C64 magazine (64'er) by a lawyer....