I think to find it funny you have to have had experience of the Services in the 1960s and early 70s.
I was part of the Air Training Corps back then and found the show hysterically funny: I'd met people who matched most of the characters, especially the dimwit Officer...!!
But it is Homophobic, Racist and most other things that melt snowflakes, so sadly it will never be shown by the BBC, despite bing a good example of social history.
Similarly I was on ATC summer camp at RAF Ta'Qali, Malta GC, in 1962, doing press-ups as part of our morning PT regime. I was clearly doing it wrong because suddenly the drill sergeant bent down and bellowed in my ear "what do you think you are doing, laddie, shagging an ant?". Whereupon the entire Flight collapsed in a heap, laughing.
As to IAHHM, I thought the characterisations were spot-on, especially Michael Bates as Ranji. Snowflakes must remember he was
acting, for goodness sake. I cannot abide revisionism.