Many ordinary social interactions have become sins recently. Saying anything that could be interpreted as offensive poses a very real risk to your career, the list of potentially offensive things is incredibly long, and gets longer with each passing moment as novel outrages pop up in all corners of the world.
You can still be kind, empathetic and polite to everybody you work with. But avoiding authentic personal relationships at work is very sensible, along with having very clear personal boundaries. Normal colleagues can form cliques of people they trust, but it’s not a great outcome for management to be participating in that, even though that’s what usually happens.
But inappropriate jokes about firing people and the like are not "ordinary social interactions" with aspects "that could be interpreted as offensive", they are an objectively oppressive and distressing behaviour that even the least upset subordinates of such a manager recognize as inappropriate.
I don’t know why this is being downvoted - it’s good advice. You should adopt a “work persona” that elides the riskier elements of your true self.
“Bring your true self to work” and other modern workplace nonsense is risky advice to take seriously. It’s mostly a coded communication that does not mean what it appears to on the surface.
You can still be kind, empathetic and polite to everybody you work with. But avoiding authentic personal relationships at work is very sensible, along with having very clear personal boundaries. Normal colleagues can form cliques of people they trust, but it’s not a great outcome for management to be participating in that, even though that’s what usually happens.