Funny you should say that but perhaps that's not necessarily true.

https://www.computerworld.com/article/3597949/everything-you...

https://www.imore.com/tests-show-apples-m1-emulates-x86-fast...

Demoscene code in particular... especially demos in the 1K and below (sizecoding) range, which basically amount to very carefully handwritten Asm. I'd expect the x86-to-ARM translation to not do so well in that case, given that it's probably tuned toward typical compiler output.

Depends largely on the code, lots of people show the M1 doing just fine running (translated) x86 code.

Apparently even this is not always the case(!)

https://www.macrumors.com/2020/11/15/m1-chip-emulating-x86-b...