I think you need to carm down in more ways than one. Stop virtue signalling and taking this moral high ground just because you have a relative who works in the industry. I do love how some folk on this forum become the thought police and must know what your thinking whilst you type.
I always try to have a laugh with staff on board and never had a single complaint and if I ever over stepped the mark I would expect the cabin manager to give me a good talking to. Actually I would expect it.and Marshall to meet me at the other end.
Having a bit of banter isn't for me talking to them in a manner that would get the thought police involved for offending folk and/or being derogatory. It's helping make the flight go quicker and helps keep morale up. I have called them air stewards/Air stewardesses since I can remember and that will never change.
If you don't like it, then lump it.
Other than that the Stewards/Stewardesses on BA are pretty good in general. Can be hit and miss at certain times of year or if they been called in off standby. I find the ones going to a location they want to visit gives them that extra spring in there step. Helps that many of them follow myself and likewise in return on Instagram and you do get to see beyond what you see when you board.
Still a long way off Qantas staff mind