You're completely right. The offhand tone many have adopted is how they might react to a purely technical piece, rather than someone's genuine pain exposed to their view. It would, after all, not be wildly out of place to react to a technically detailed root cause analysis document by questioning some of its assertions that struck readers as overreaching.

For my own part, when I find myself reacting to someone's tone I sometimes find it valuable to pause and consider why they would adopt it. It can help me separate the other person's tone from the real, valid, lived experience that is my internal emotional reaction.

Empathy cannot just be a thing I demand of others.