[Wistar]

Wow. With "secondhand embarrassment" you have deftly labeled a feeling I have had so many times in my life but have never been able to succinctly name.

[codethief]

That term even has its own Wikipedia page:

https://en.m.wikipedia.org/wiki/Vicarious_embarrassment

[Semaphor]

It’s a pretty popular German word as well: https://en.wiktionary.org/wiki/fremdsch%C3%A4men

[derevaunseraun]

It's also called 'cringe' in gen Z speak