On the same note, does it mean that passenger complaint letters about FAs will not be reflected in performance appraisal as well?

I once was on a MNL - HKG flight in Y, and there was this FA (I clearly remember her name from the name tag) who was sulky throughout the flight and curt to the passengers who were mainly Philipinos (I notice this "attitude" by FAs in Y happens mainly on HKG - MNL - HKG flights) that generally made my entire flight experience very uncomfortable. I had wanted to write in to notify that such attitude was unacceptable, but wasn't sure if it would be taken at all seriously.