Wow. Wow. Is this really a thing, excusing forced trauma by claiming it makes people better?
Of course that's no excuse to downplay the occupational hazard of PTSD. But it's a real thing; facebook didn't make it up.
For example, some people take traumatic stress at really poorly (PTSD). Some people develop a world outlook to the tune of "well no matter what happens life is looking up from here" (post traumatic growth).
The counselor is looking at the glass half full. You kind of need to be a glass half full person to persist in that line of work.
The actual benefit of what you describe as growth is quite low to offset clinical PTSD which affects life quite a lot.
Furthermore there are many factors in play. The nature of the trauma and the predisposition of the person experiencing the trauma both seem to play a big role in whether or not post-traumatic growth is likely to occur. People with social support networks or spirituality are more likely to experience post-traumatic growth. Perhaps for related reasons, trauma that is systematic or collective (such as being a prisoner of war) is more likely to induce post-traumatic growth than trauma which is personal or individual (e.g. sexual assault.)
(Furthermore, no matter how distasteful the possibility may seem, it is possible that post-traumatic growth can take people past whatever their baseline was prior to the inducement of PTSD.)
Other people experiencing post-traumatic growth does not offset all that. It does not make for losses and answer to "is it overall beneficial for people to go through that" is still no.
Counselor answer suggests yes and that is what people take issue with. Whether one can have PTSD and post traumatic growth at the same time is different question.