What I've learned from this comment is that there is an extremely small percentage of gals who may dislike the term ladies based on a very obscure reason, so until they tell me their personal objections the reasonable thing is to go with the common societal usage of the word.

You're probably getting down voted because it'd be the same as if I got on my high horse and replied, "well you oughta learn that some people don't even like the word 'person' because it reminded them of existing".

Like sure, that happened to you and it's great that you can now refer to your friend the way they prefer. But that's such a niche situation that I don't think it should be conveyed in a manner as if people were inadequate for not knowing. Makes a good story to tell though.

If you'd just said "fun fact, some people blah blah blah" it carries a very different tone then "good start, now learn that blah blah blah"

One implies it is an experience you had, the other implies it is an experience that all others should've known.