I interviewed a young man who was doing this kind of work for about six months in Ireland a while back for a completely different role. It was quite clearly mentally taxing and he broke down crying mid-interview.

I ended up canceling my following meeting and talking through things with him.

He was close to suicide, had cut contact with most people in his life and said that he hadn't been able to sleep or think straight since he started the work. Unfortunately I couldn't offer him any work, only a shoulder to cry on and a promise that there was beauty in the world as well.

I never thought a job could do so much mental damage to someone, but these jobs are horrible.