Interesting responses.
My thoughts are that gallows humour is one of those things that is so difficult to 'get right' without offending others, iyswim.
I feel that it's great to have a joke and laugh at dreadful stuff that's happening directly to you, if you are that way inclined obviously, and that jokes help us get through the worst of times. But there's something about people making gallows humour type of jokes about stuff that's absolutely not happening directly to them that I find a bit troubling.
I have a(n actually pleasant) friend, who's extremely proud of their vocal gallows humour, and they keep annoying and/or offending people. They are proud to the point of their sense of humour that they mention it about themselves at any possible opportunity, often in a faintly challenging way. It's actually quite boring though.
Then they get really angry and accuse people of having no sense of humour, but I'm not sure it's that simple.
What do others think?