Because we don't see what real, actual, guillotines do.
I accidentally saw a guillotine-execution on DuckDuckGo ( they used to be much worse than they are now, for including stuff you don't want to see )
and .. it's kinda hard to communicate how WRONG that is, to chop a human-life to that degree of .. to just-now-dead..
interesting: I can't communicate how wrong/horrible it was, through words!
Anyways, there's some German word, looks sorta like schedenfruede or something like that..
it means "finding enjoyment in other people's suffering", and old-people don't find it funny, generally, because old-people have experienced enough diversity-of-suffering to be able to understand other-people's perspectives..
The more one sees what people mean, the more one has to choose a self-defense-for-one's-psyche strategy:
either sensitivity, in which case one has to avoid the coarser & worse stuff in life, systematically .. XOR
de-sensitization, in which case one can joke about it, push it, even do it, because one is making one's essence become mechanical/dead to what one's engaging.
There's a story of Hinduism, during the British rule of India..
Some privileged people got together to do some hunting..
1 of those was Indian, he'd used guns, before, he just hadn't destroyed someone's life, before..
After he shot a naturally-magnificent animal, & saw it dying as a result of his bullet, he put down his rifle, & left, never returning to that kind of culture, again..
IF sensitivity is one's path, like making oneself into a combination microscope+telescope, spiritually, THEN .. this kind of reaction becomes inevitable.
You just can't accept what a real guillotine-execution is.
Joking-about such stuff is fine until you actually understand what it means .. & then .. you can't joke about it, anymore.
Like Ukranians are unlikely to be able to joke about what Russia did to Mariupol, you know?
It's too live-wire fresh a wound..
Having seen what a 1-to-2-second long video of a guillotine-execution looked like, I'd now say that only the evil could do them, repeatedly.
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