Honestly, I think I’d be a bit taken aback by this as well.
I’m probably very similar to you. When everything is going wrong and the workload is ridiculous, I’ll generally make a sarcastic comment about it, have a laugh and crack on. That doesn’t mean I don’t care or that I’m oblivious to how much pressure everyone is under. It’s just how I deal with stressful situations.
Life experience also massively affects your perspective. I’ve dealt with some pretty significant personal stuff over the years, so my threshold for what I consider a genuine crisis is probably quite high. Work can be stressful, annoying and difficult without me feeling devastated by it. And I don’t think that means I lack empathy. I can see that somebody else is struggling and support them without needing to mirror their emotions.
I would take seriously the bit about humour perhaps coming across as dismissive, because that could be a genuine blind spot. If several people are interpreting something differently from how you mean it, it’s worth understanding why. But beyond that, I’d want specifics.
What does your manager actually mean by a “normal range of emotions”? What behaviour has she seen that concerns her? What would she have expected you to do instead?
Because “you don’t cry at work” is a very odd measure of vulnerability or empathy!
To me, vulnerability is being able to say “I got that wrong”, “I need help”, “I don’t know” or “I’m struggling with this”. It isn’t having to visibly demonstrate distress whenever something difficult happens.
So I’d listen to the feedback, ask for examples and reflect honestly on whether there’s anything useful in it. But I definitely wouldn’t feel obliged to manufacture an emotional response just because someone else thinks that’s how you’re supposed to react.
Some of us swear, make inappropriate jokes about the impending disaster and get on with fixing it.