I suspect this is fair, when you talk about the things you dealt wirh you do so like only you had to do that, where as they all do, and still are, it’s literally the job, your write about it with horror.
You did it for a long time successfully but ultimately you should have left the police when it started to impact your mental health.
i have some very senior police officers in my family and the things they have seen and dealt with over the years is horrendous, the worst crimes, the victims there in front of them, the worst sort of criminals, things I couldn’t even write here they are so so awful, and beyond comprehension.
beinf a call handler wasn’t for you, and that’s ok, your colleagues are still in there manning the phones, the front line officers still dealing with it in person. We all have different skills, you clearly have many, but when a job is not something we have the ability to do without impact we move on.
its sad they had to do that and not you, but it doesn’t mean it was unfair.