Lol, man, maybe I'm deluded, but getting a PIP for medical issues only means you work for scumbags. It does not indicate anything about your "business language" needing work.

I've seen managers struggle to emotionally justify firing incompetent dolts. They didn't go "heh, what's the smartest way to scape goat this guy out of here"? Honestly, I would've had a much easier time, but I would've done it in a straightforward way.

If anything, I predict the "common knowledge trait" to shake out of society is "being a good person", and it shook out millennia ago and is pretty common (too common, if anything). If you're not, nobody'll wanna work with you.