It's not ridiculous at all.
Again, the reason why you perceive psychiatrists not to to be held to the same scrupulous standards as consultants in other disciplines is precisely because what they do is tantamount to an esoteric black art where mistakes are absolutely inevitable.
A brain surgeon can cut someone's skull open and operate on their brain forearmed with knowledge of precisely what the purpose is and how they need to treat the patient because physical ailments can be detected with scans and imaging.
There is no such equivalent for psychiatry. You can not cut someone's head open and take a slice of their brain matter to determine whether what you are dealing with is CTE or a schizophrenic illness. There is no blood test for CPTSD. They will run tests if you are being investigated for Bipolar, but only to check thyroid function, it doesn't come back with a marker saying "this person is Bipolar". Without an extensive knowledge of a patient's personal history, it's impossible to tell if an agitated or depressed state is due to an environmental factor or some underlying health condition. How is a psychiatrist who has met you for the first time five minutes ago supposed to know? Especially so when your agitated/subdued state means they aren't going to get anything meaningful out of you anyway, and you've had no prior engagement with mental health services to offer any leads?
Psychiatric medical model is far from perfect and there isn't really any serious opposition to that contention, but the mistakes made are more often a result of an imperfect understanding of the human brain and an absence of diagnostic tools compared to disciplines concerned with physical health, and not just the sheer incompetence or intransigence of mental health professionals. To coin a phrase, you can only work with the tools at your disposal, and if the tools are inadequate you will end up with unsatisfactory results. What is needed in order to improve psychiatry is far more serious investment in all aspects of mental health provision, not just chasing after existing psychiatrists with a shitty stick because of perceived wrongdoing. Where there is obvious shortfall in care it needs addressed, but the vast majority of psychiatrists are, like the overwhelming majority of other doctors, genuinely trying to help despite the fact they frequently get things wrong. That isn't a personal failing, it's part and parcel of psychiatry.