At the end of the day, there are good crew and bad crew, just as there are lovely passengers and vile passengers, great flight crew and not so great flight crew etc. You've only got to look through some of the threads on this forum to see that.
I'm sure I'm not the only one that has sometimes cringed when hearing the way a crew member has spoken to a passenger and if I'm totally honest, nor can I put my hand on my heart and say I have never dealt with a situation badly, especially at the end of a long, difficult day. I regret those moments and where possible, have always apologised and then hopefully, learnt from my mistakes.
I have also been on the other side, with a passenger who is going to find something wrong, no matter what we do. That's part of being human and in my experience, most of the time, it works well!
JSL