OP I don't understand how if everyone had an LPA in place, it would save a vast amount for the NHS and social care. Can you explain. They usually don't go much beyond allowing the next of kin to make decisions on that person's behalf if they loose capacity which is the norm anyway. An advance directive isn't usually much more than a DNR is it? Although maybe it can include treatment too - such as antibiotics being given to a person in hospital via IV which may only prolong their suffering and may not be in their best interests.
My late mum didn't have an LPA. She went into hospital and was moved to a care home when she required nursing care and sometimes 1:1 care over a 2 year period. She lacked capacity and was on a DOLS for a time due to her confusion and demanding to go home. She had progressive vascular dementia and it is the most cruel and debilitating disease.
As next of kin I was consulted every step of the way. At some point after she deteriorated in the care home, I agreed to a DNR, and when it came to her last 24 hours I was asked if I wanted them to send her to hospital or keep her at home. I chose her staying at home and stayed with her until she died peacefully (she had pneumonia). There would have been no point them trying to rally her with antibiotics for a few days or weeks removing a very confused lady from her usual surroundings. Her quality of life was abysmal by that point. I agreed because I thought it was what she would have wanted but also on her GPs advice - who said that is what she would want/choose if it were her mum.
Not having a LPA made no difference to the care she received or the cost to the NHS - which was very high as she was fully funded. She was never at deaths door until the very last day or two and never hospitalised during the 2 years she was in the care home. How would an LPA have helped here?
I already had third party access to her bank accounts which she granted mainly due to her becoming less mobile and unable to go to the bank. She could not cope with online banking as she never had a computer or did telephone banking (she struggled with new things long before she was diagnosed with dementia and was also quite deaf). She trusted me to look after her affairs.
Surely in most cases, the next of kin just speaks for their relative when they are unable to do so? A LPA would be more relevant if you had multiple people involved (or none) and you wanted to nominate someone as your representative. I was an only child and my mum was a widow so ultimately it was up to me and her doctors to decide what was in her best interests. I think most people would want to be treated/resuscitated anyway until their situation becomes truly intolerable.
My mum was asked if she wanted to be on a DNR some time earlier (while she still had capacity) and at that time she said no. While her enjoyment of life was hindered by her having a stroke/mobility issues and her deafness, she still enjoyed visits with friends and family and being a grandma. Progressive vascular dementia strips all that away.
I am not even sure in an emergency situation, the information in the LPA or AD/DNR would be easy to access. A different matter if you are in hospital already or in a care home and they have the records.
I imagine this is most people's experience and why lots of people don't bother with an LPR. They don't think they need one. Your post made me wonder if I should get one but my son is an only child and I am happy for him to make any decisions on my behalf when the time comes.