A more TLDR article about this: https://www.extremetech.com/defense/173108-researchers-crack-the-worlds-toughest-encryption-by-listening-to-the-tiny-sounds-made-by-your-computers-cpu
FAQs from the researchers: https://web.archive.org/web/20230130225254/http://www.cs.tau.ac.il/~tromer/acoustic/
You reminded me about this video https://www.youtube.com/watch?v=eUzB0L0mSCI